Augmented reality display system for the assessment and correction of neurological disorders, including disorders of visual processing and perception

Abstract

Providing an augmented reality display system for the assessment and correction of neurological disorders, including disorders of visual processing and perception. In some embodiments, a display system including a head-mountable augmented reality display is configured to perform a neurological analysis and provide sensory aids based on environmental triggers associated with a neurological disorder. Performing the neurological analysis may include determining a response to a stimulus by receiving data from one or more inwardly directed sensors and identifying a neurological disorder associated with the response. In some embodiments, the sensory aids may include reminders, alerts, or virtual content that change properties, e.g., the color of a real object.

Description

[Technical Field]

[0001] (Priority Claim) This application claims the benefit of priority under 35 U.S.C. 119(e) of U.S. Provisional Application No. 62 / 352,539, filed June 20, 2016, U.S. Provisional Application No. 62 / 366,555, filed July 25, 2016, and U.S. Provisional Application No. 62 / 440,291, filed December 29, 2016. The entire disclosure of each of these priority documents is incorporated herein by reference.

[0002] (Incorporated by reference) This application is incorporated herein by reference in its entirety. This application is incorporated herein by reference in its entirety. No. 9,417,452 (issued August 16, 2016), U.S. Application No. 14 / 331,218 (filed July 14, 2014, published October 29, 2015 as U.S. Patent Application Publication No. 2015 / 0309263), and U.S. Application No. 15 / 072,290 (filed March 16, 2016, published September 22, 2016 as U.S. Patent Application Publication No. 2016 / 0270656), each of which is incorporated by reference in its entirety.

[0003] The present disclosure relates to display systems, and more particularly to augmented reality display systems. [Background technology]

[0004] Modern computing and display technology has facilitated the development of systems for so-called "virtual reality" or "augmented reality" experiences, in which digitally reproduced images or portions thereof are presented to a user in a manner that appears or can be perceived as real. Virtual reality or "VR" scenarios typically involve the presentation of digital or virtual image information without transparency to other actual real-world visual input, while augmented reality or "AR" scenarios typically involve the presentation of digital or virtual image information as an augmentation to the user's visualization of the real world around them. Mixed reality or "MR" scenarios are a type of AR scenario that typically involve virtual objects integrated into and responsive to the natural world. For example, MR scenarios may include AR image content that appears blocked by or is perceived to otherwise interact with objects in the real world.

[0005] 1, an augmented reality scene 1 is depicted in which a user of the AR technology sees a real-world park-like setting 1100 featuring people, trees, background buildings, and a concrete platform 1120. In addition to these items, the user of the AR technology also perceives that they are "seeing" "virtual content," such as a robotic figure 1110 standing on the real-world platform 1120 and a flying, cartoon-like avatar character 1130 that appears to be an anthropomorphic bumblebee, even though these elements 1130, 1110, do not exist in the real world. The human visual perception system is complex, making it difficult to create AR technology that facilitates a comfortable, natural-feeling, and rich presentation of virtual image elements among other virtual or real-world image elements.

[0006] The systems and methods disclosed herein address various challenges associated with AR or VR technology. Summary of the Invention [Means for solving the problem]

[0007] In some embodiments, the display system includes a head-mountable augmented reality display configured to output light with a variable wavefront divergence and display virtual content. The display system also includes one or more inwardly directed sensors, one or more outwardly directed sensors, one or more processors, and one or more computer storage media storing instructions that, when executed by the one or more processors, cause the one or more processors to perform various operations. The operations include performing a neurological analysis, determining an environmental trigger associated with a neurological disorder, monitoring the surrounding environment with the one or more outwardly directed sensors, detecting the presence of the environmental trigger in the surrounding environment, and providing a sensory aid based on the detected presence of the trigger variable. Performing the neurological analysis includes determining a response to a stimulus by receiving data from the one or more inwardly directed sensors and identifying a neurological disorder associated with the response.

[0008] In some other embodiments, the display system includes a head-mountable augmented reality display configured to output light with a variable wavefront divergence and display virtual content. The display system also includes one or more inwardly directed sensors, one or more processors, and one or more computer storage media storing instructions that, when executed by the one or more processors, cause the one or more processors to perform various operations. The operations include performing a neurological analysis by receiving data from the one or more inwardly directed sensors, determining a response to a stimulus, and identifying a neurological disorder associated with the response.

[0009] In yet another embodiment, a method is implemented by a display system comprising one or more processors, one or more inwardly directed sensors, and a head-mounted display, the method including performing a neurological analysis by collecting data from the one or more inwardly directed sensors, determining a user response to a stimulus, and identifying a neurological disorder associated with the response.

[0010] Additionally, various innovative aspects of the subject matter described in this disclosure can be implemented in the following embodiments. Embodiment 1: A display system comprising: 1. A head-mounted display configured to project light onto a user and display augmented reality image content on multiple depth planes, comprising: a display comprising one or more waveguides configured to project light to a user, the one or more waveguides further configured to transmit light from an ambient environment to the user; providing a stimulus to the user; determining a user's response to the stimulus; determining the presence of a neurological disease or condition in the user associated with the response; A display system configured as follows. Embodiment 2: A display system as described in embodiment 1, wherein the stimulus includes augmented reality image content. Embodiment 3: A display system described in any of embodiments 1-2, wherein the display system is configured to display to the user a list of neurological diseases corresponding to the response. Embodiment 4: A display system according to any one of embodiments 1-3, wherein the neurological disease is a neurological abnormality. Embodiment 5: A display system according to any of embodiments 1-4, wherein the display system is configured to communicate a list of neurological diseases to a clinician. Embodiment 6: A display system described in any of embodiments 1-5, wherein the display system is configured to communicate a list of neurological diseases to one or more other users. Embodiment 7: A display system comprising: providing stimuli by displaying multiple images to a user, one of the images being on a different depth plane than another of the images; The user's eye accommodation, convergence and divergence state and / or other efferent responses Measure determining the image as perceived by the user by matching the measured accommodation, convergence state, and / or other efferent responses with expected accommodation and / or convergence state for one of the images or another of the images; The reaction is judged by 7. A display system according to any one of embodiments 1 to 6, configured as follows: Embodiment 8: A display system as described in any of embodiments 1-7, wherein the display is configured to continuously display augmented reality image content to the user three or more times while the user is wearing the display. Embodiment 9: A display system according to any of embodiments 1-8, wherein the display is configured to display the augmented reality image content five or more times. Embodiment 10: The display system performs the following sequence multiple times over several months: providing a stimulus to the user; determining a user's response to the stimulus; determining the presence of a neurological disorder associated with the response in the user; 10. A display system according to any one of embodiments 1 to 9, configured to automatically perform the above. Embodiment 11: A display system comprising: a head-mounted display configured to project light to a user and display augmented reality image content on multiple depth planes, the display comprising one or more waveguides configured to project light to the user, the one or more waveguides further configured to transmit light from a surrounding environment to the user; determining a user's response to the stimulus; determining the presence of a neurological disorder associated with the response in the user; A display system configured as follows. Embodiment 12: A display system described in any of embodiments 1-11, wherein the display system is configured to provide information associated with a neurological disease to a population of other users. Embodiment 13: A display system as described in embodiment 12, wherein the display system is configured to determine a neurological disease based on criteria determined from a population of other users. Embodiment 14: A display system according to any of embodiments 12-13, wherein the display system is configured to read out criteria for a subset of the population based on criteria corresponding to a user. Embodiment 15: A display system described in any of embodiments 12-14, wherein the display system is configured to dynamically modify the criteria by providing information associated with neurological diseases to a population of other users. Embodiment 16: A display system, comprising: 1. A head-mounted display configured to project light onto a user and display augmented reality image content on multiple depth planes, comprising: a display comprising one or more waveguides configured to project light to a user, the one or more waveguides further configured to transmit light from an ambient environment to the user; determining whether the stimulation is associated with a neurological disorder; Display sensory aids for neurological disorders, A display system configured as follows. Embodiment 17: A display system, comprising: 1. A head-mounted display configured to project light onto a user and display augmented reality image content on multiple depth planes, comprising: one or more waveguides configured to project light to a user, the one or more waveguides further configured to transmit light from the surrounding environment to the user; one or more sensors configured to monitor the environment; and a display, determining the user's expected emotional response to objects in the environment; determining whether the user's anticipated emotional response to the object is a target for modification; Modifying a user's expected emotional response to an object by presenting augmented reality content to the user; A display system configured as follows. Embodiment 18: A display system as described in embodiment 17, wherein the augmented reality content is augmented reality image content. Embodiment 19: A display system according to any of embodiments 17-18, wherein the object is associated with the user's phobia. Embodiment 20: A display system as described in any of embodiments 17-19, wherein the display system is configured to visually overlay augmented reality content onto the object. Embodiment 21: A display system comprising: determining a distance of an object from the user and presenting augmented reality content that overlays the object on a depth plane corresponding to that distance; A display system according to any one of embodiments 17-21, configured as follows: Embodiment 22: A display system, comprising: 1. A head-mounted display configured to project light onto a user and display augmented reality image content on multiple depth planes, comprising: one or more waveguides configured to project light to a user, the one or more waveguides further configured to transmit light from the surrounding environment to the user; a sensor configured to monitor an environment; a display; determining an expected physical or behavioral response of the user to objects in the environment; determining whether an expected user physical or behavioral response to the object is a target for modification; Modifying the user's expected physical or behavioral response to the object by presenting augmented reality content to the user; A display system configured as follows. Embodiment 23: A display system as described in embodiment 1, wherein the provided stimuli include one or more images presented to at least one eye of the user. Embodiment 24: One or more images are a first image presented to a first eye of a user; a second image presented to a second eye of the user; and 24. The display system of embodiment 23, wherein the second image is different from the first image. Embodiment 25: A display system described in any of embodiments 23-24, wherein the one or more images include a first image and a second image presented to the same eye of the user, the second image being different from the first image. Embodiment 26: A display system described in any of embodiments 23-25, wherein the second image differs from the first image in contour, color, brightness, flicker rate, or contrast. Embodiment 27: A display system described in any of embodiments 23-26, wherein the first image includes a first portion, the second image includes a second portion, and the first portion and the second portion form a coherent image. Embodiment 28: A display system described in any of embodiments 23-27, wherein the first image comprises a static image and the second image comprises a series of dynamic images. Embodiment 29: A display system described in any of embodiments 23-28, wherein the first image includes a stationary image and the second image includes a moving image. Embodiment 30: A display system described in any of embodiments 23-29, wherein one of the one or more images includes a stationary portion and a moving portion. Embodiment 31: The display system of any of embodiments 23-30, wherein the one or more images include one or more images with different contrast.Embodiment 32: The display system of any of embodiments 23-31, wherein the response includes a visual perception of the user in response to the one or more images presented. Embodiment 33: A display system as described in embodiment 32, wherein the response comprises a perceptual state of dominance or inhibition. Embodiment 34: The reaction suppression of one of the one or more images; Reconstruction of a portion of one or more images; or loss of at least a portion of one of the one or more images; 34. A display system according to any one of embodiments 32-33, comprising: Embodiment 35: A display system described in any of embodiments 33-34, further comprising a user interface for measuring a perceptual state of dominance or inhibition. Embodiment 36: A display system described in any of embodiments 33-35, wherein the display system is configured to infer a dominant or inhibited perceptual state using data from optokinetic nystagmus (OKN), visual evoked potentials (VEP), magnetoencephalography (MEG), or blood oxygen level-dependent (BOLD) contrast imaging using functional magnetic resonance imaging (fMRI). Embodiment 37: A display system described in any of embodiments 33-36, wherein the display system is configured to determine the presence of a neurological disease associated with visual processing in a user. Embodiment 38: A display system as described in embodiment 1, further comprising an electrode configured to measure electrical potentials at or associated with the user's head from at least one or more sensors. Embodiment 39: A display system as described in embodiment 38, wherein the electrodes are configured to be placed at multiple locations on the user's head and the display system is configured to simultaneously derive potential measurements from the multiple locations. Embodiment 40: A display system described in any of embodiments 38-39, wherein the display system is configured to present the stimulus to one eye of the user. Embodiment 41: A display system described in any of embodiments 38-40, wherein the display system is configured to present stimuli to both eyes of the user simultaneously. Embodiment 42: A display system described in any of embodiments 38-41, wherein the display system is configured to present a checkerboard stimulus that alternates between colors. Embodiment 43: A display system described in any of embodiments 38-42, wherein the display system is configured to present stimuli that change size within a certain time interval. Embodiment 44: A display system described in any of embodiments 38-43, wherein the display system is configured to determine the minimum change that produces a response. Embodiment 45: A display system described in any of embodiments 38-44, wherein the display system is configured to present a stimulus that changes color. Embodiment 46: The display system of embodiment 45, wherein the color varies to different shades of similar colors. Embodiment 47: A display system described in any of embodiments 38-46, wherein the display system is configured to present stimuli that vary in brightness. Embodiment 48: A display system described in any of embodiments 38-47, wherein the display system is configured to present the stimulus over a portion of the user's field of view. Embodiment 49: A display system described in any of embodiments 38-48, wherein the display system is configured to present the stimulus over a portion of the user's field of view. Embodiment 50: A display system described in any of embodiments 38-49, wherein the display system is configured to present stimuli on multiple depth planes. Embodiment 51: A display system described in any of embodiments 38-50, wherein the display system is configured to present stimuli that alternate between different portions of the user's field of view, and the display system is configured to measure at least the difference in evoked event-related potentials between the stimuli that alternate between the different portions. Embodiment 52: A display system described in any of embodiments 38-51, wherein the display system is configured to present stimuli that change between at least two colors. Embodiment 53: A display system as described in embodiment 52, wherein the display system is configured to present the stimulus to the user's entire field of view. Embodiment 54: A display system described in any of embodiments 38-53, wherein the display system is configured to present stimuli that change location from one area on the field of view to another. Embodiment 55: A display system described in any of embodiments 38-54, wherein the display system is configured to present stimuli that change orientation. Embodiment 56: A display system described in any of embodiments 38-55, wherein the display system is configured to present stimuli with varying boundary sharpness. Embodiment 57: A display system described in any of embodiments 38-56, wherein the display system is configured to present stimuli that vary the boundary contrast. Embodiment 58: A display system described in any of embodiments 38-57, wherein the display system is configured to present stimuli that change characteristics at specific frequencies. Embodiment 59: A display system as described in embodiment 58, wherein the display system is configured to measure the response in the user at varying frequencies of the stimulus. Embodiment 60: A display system described in any of embodiments 38-59, wherein the display system is configured to present stimuli including random dot stereograms. Embodiment 61: A display system described in any of embodiments 38-60, wherein the display system is configured to compare the measured response with a predetermined response indicative of a normal response. Embodiment 62: A display system described in any of embodiments 38-61, wherein the display system is configured to compare the measured response with a predetermined response indicative of a particular neurological abnormality. Embodiment 63: A display system as described in embodiment 1, wherein the provided stimulus comprises bright light. Embodiment 64: A display system as described in embodiment 63, wherein the user's response includes a reduced rate or reduced amplitude at which the pupil of the user's eye constricts. Embodiment 65: A display system described in any of embodiments 63-64, wherein the neurological disease is associated with at least one of a lesion of the ipsilateral optic nerve, a lesion of the pretectal area, a lesion of the ipsilateral parasympathetic nerve progressing within the III cranial nerve, a lesion of the sphincter pupillae of the iris, a lesion of the contralateral optic nerve, epilepsy, anxiety disorder, dependency, addiction, stroke, cerebral aneurysm, Guillain-Barré syndrome, and traumatic brain injury. Embodiment 66: A display system described in any of embodiments 63-65, wherein the provided stimulus comprises a light spot that alternates back and forth between the user's first eye and second eye. Embodiment 67: A display system as described in embodiment 66, wherein the user's reaction includes dilation of the pupil of the user's eye when illuminated by the light spot. Embodiment 68: A display system described in any of embodiments 66-67, wherein the neurological disease is at least one of multiple sclerosis, neuromyelitis optica, optic neuritis, or traumatic optic neuropathy. Embodiment 69: A display system as described in embodiment 1, wherein the provided stimulus includes an object that is moved from the far-distance visual zone to the near-distance visual zone. Embodiment 70: A display system as described in embodiment 69, wherein the user's reaction includes a miosis of the pupils of one or both of the user's eyes as the object is moved from the far-distance visual zone to the near-distance visual zone. Embodiment 71: A display system described in any of embodiments 69-70, wherein the neurological disease is associated with at least one of a lesion of the ipsilateral optic nerve, a lesion of the ipsilateral parasympathetic nerve progressing into the III cranial nerve, a lesion of the pupillary sphincter of the iris, a bilateral lesion of the pathway from the optic tract to the visual cortex, cognitive impairment, dementia, Alzheimer's disease, dementia with Lewy bodies, and cortical blindness. Embodiment 72: A display system as described in embodiment 1, wherein the provided stimulus comprises an object that is moved across the horizontal or vertical field of view. Embodiment 73: A display system as described in embodiment 73, wherein the user's response includes an impairment in smooth movement of one or both of the user's eyes along a horizontal or vertical axis within the user's field of view. Embodiment 74: A display system described in any of embodiments 72-73, wherein the neurological disease is associated with at least one of cognitive impairment, Parkinson's disease, dementia, Alzheimer's disease, frontotemporal dementia, progressive supranuclear palsy, addiction, dependency, traumatic brain injury, and cortical blindness. Embodiment 75: A display system as described in embodiment 1, wherein the provided stimulus includes an object that is moved toward one or both eyes of the user. Embodiment 76: A display system as described in embodiment 75, wherein the user's response includes deviation of one or both of the user's eyes along a non-neutral direction. Embodiment 77: A display system described in any of embodiments 75-76, wherein the neurological disease corresponds to at least one of dystonia, Parkinson's disease, corticobasal degeneration, or Lewy body degeneration. Embodiment 78: A display system as described in embodiment 1, wherein the provided stimulus includes a first object at a first location and a second object at a second location, the first and second locations being spaced apart. Embodiment 79: A display system as described in embodiment 78, wherein the user's response includes measuring the speed, amplitude, or frequency of saccadic movements of one or both of the user's eyes. Embodiment 80: A display system described in any of embodiments 76-79, wherein the neurological disease is associated with at least one of cognitive impairment, dementia, Alzheimer's disease, Huntington's disease, Parkinson's disease, corticobasal degeneration, dementia with Lewy bodies, and progressive supranuclear palsy. Embodiment 81: A display system as described in embodiment 1, wherein the provided stimuli include an immobile target and a different object located on either side of the immobile target. Embodiment 82: A display system as described in embodiment 81, wherein the user's response includes an inability to inhibit a reflex saccade. Embodiment 83: A display system described in any of embodiments 81-82, wherein the neurological disease is associated with at least one of dementia, Alzheimer's disease, Huntington's disease, Parkinson's disease, corticobasal degeneration, dementia with Lewy bodies, frontotemporal dementia, and schizophrenia. Embodiment 84: A display system as described in embodiment 1, wherein the provided stimulus comprises a light and dark stripe that is moved across the user's field of view. Embodiment 85: A display system as described in embodiment 84, wherein the user's response includes movement of the user's eyes across the field of view followed by movement to the midline at a speed that does not exceed the movement across the field of view. Embodiment 86: A display system described in any of embodiments 84-85, wherein the neurological disease is associated with at least one of hemispatial neglect, multiple sclerosis, neuromyelitis optica, ataxia, addiction, and stroke. Embodiment 87: A display system as described in embodiment 1, wherein the provided stimuli include flickering light spots and non-flickering light spots. Embodiment 88: A display system as described in embodiment 87, wherein the user's response includes a change in the hue perception of the flickering light spots. Embodiment 89: A display system described in any of embodiments 87-88, wherein the neurological disease corresponds to reactive optic neuritis. Embodiment 90: The display system of embodiment 1, wherein the provided stimuli include objects that are rapidly moved toward one or both eyes of the user from different directions. Embodiment 91: A display system as described in embodiment 90, wherein the user's reaction includes an inability to blink. Embodiment 92: A display system described in any of embodiments 90-91, wherein the neurological condition corresponds to a coma state. Embodiment 93: A display system as described in embodiment 1, wherein the provided stimulus includes an object that is displayed simultaneously on both sides of the user. Embodiment 94: A display system as described in embodiment 93, wherein the user's reaction includes an inability to perceive objects on one side when displayed simultaneously on both sides of the user. Embodiment 95: A display system described in any of embodiments 93-94, wherein the neurological disease is associated with stroke. Embodiment 96: A display system as described in embodiment 16, wherein the neurological condition includes increased neuroplasticity. Embodiment 97: A display system as described in embodiment 16, wherein the display system is configured to provide stimuli to a user and enhance neuroplasticity. Embodiment 98: A display system as described in embodiment 97, wherein the stimulus is provided as part of a video game. Embodiment 99: A display system as described in embodiment 16, wherein the sensory assistance includes guided image therapy. Embodiment 100: A display system as described in embodiment 16, wherein the sensory assistance includes guided images and music therapy. Embodiment 101: A display system as described in embodiment 16, wherein the sensory aid includes a visual stimulus associated with positive feedback by the user. Embodiment 102: A display system as described in embodiment 16, wherein the sensory aid includes a visual stimulus associated by the user with negative feedback. Embodiment 103: A display system as described in embodiment 16, wherein the sensory aid includes audiovisual stimuli configured to condition the user through classical conditioning techniques. Embodiment 104: A display system as described in embodiment 16, wherein the sensory aid includes audiovisual stimuli configured to condition the user through operant conditioning techniques. Embodiment 105: A display system as described in embodiment 16, wherein the display system is further configured to associate a positive or negative value with the visual stimulus. Embodiment 106: The display system of embodiment 16, wherein the neurological disease includes pain. Embodiment 107: A display system as described in embodiment 106, wherein the sensory aid includes audiovisual stimuli configured to distract the user and alleviate the sensation of pain. Embodiment 108: A display system described in any of embodiments 106-107, wherein the sensory aid includes audiovisual stimuli configured to relax the user and alleviate the sensation of pain. Embodiment 109: A display system described in any of embodiments 106-108, wherein the sensory aid includes a guide image for alleviating the sensation of pain. Embodiment 110: A display system described in any of embodiments 106-109, wherein the display system further comprises a user interface element and receives user input regarding pain level. Embodiment 111: A display system described in any of embodiments 106-110, wherein the sensory aid includes audiovisual stimuli configured to modify the user's mood. Embodiment 112: A display system as described in embodiment 111, wherein the sensory aid includes a guidance image. Embodiment 113: A display system as described in embodiment 16, wherein the sensory aids include audiovisual stimuli configured to provide perceptual learning techniques and improve the user's skills and abilities. Embodiment 114: A display system as described in embodiment 16, wherein the skills and abilities include perceptual abilities. Embodiment 115: A display system as described in embodiment 16, wherein the display system is configured to provide eye movement desensitization and reprocessing (EMDR) therapy. Embodiment 116: A display system as described in embodiment 115, wherein the sensory assistance includes bilateral sensory input configured to induce lateral eye movements in the user. Embodiment 117: A display system as described in embodiment 16, wherein the display system is further configured to provide computer games tailored to improve perceptual and cognitive abilities. Embodiment 118: A display system as described in embodiment 16, wherein the display system is configured to provide auditory discrimination applications to address speech and language disorders. Embodiment 119: A display system as described in embodiment 16, wherein the display system is configured to provide a primary stimulus configured to engage a primary cognitive or sensory pathway and a secondary stimulus configured to engage a second cognitive or sensory pathway. Embodiment 120: A display system as described in embodiment 119, wherein the sensory aid includes letters or numbers associated with colors. Embodiment 121: A display system described in any of embodiments 119-120, wherein the sensory aid includes music associated with a color. Embodiment 122: The display system of any of embodiments 119-121, wherein the sensory aid includes numbers and / or letters positioned in 3D space around the user. Embodiment 123: The display system of embodiment 16, wherein the sensory aid includes a virtual reflected image of the user, a first portion of the image including an accurate depiction of the user, and a second portion of the image that is complementary to the first portion of the image including a virtual reflection of the first portion, forming a full image of the user. Embodiment 124: A display system as described in embodiment 123, wherein the display system is configured to move the entire image with left-right symmetry. Embodiment 125: A display system as described in embodiment 16, wherein the sensory assistance includes audiovisual stimuli configured to stimulate the user's senses based on the object presented to the user. Embodiment 126: A display system as described in embodiment 16, wherein the sensory aid includes audiovisual stimuli including an object at a first distance and an object at a second distance, the object at the second distance being shown as blurred or unclear. Embodiment 127: The display system of embodiment 16, wherein the display system is configured to provide speech recognition and display the recognized speech as text, and the sensory aid includes text corresponding to the speech detected by the display system. Embodiment 128: The display system of embodiment 1, further comprising a speaker configured to transmit audio content to the user's ear, wherein the stimulus includes audio content. Embodiment 129: A display system as described in embodiment 128, wherein the stimulus includes one or more instructions that are audible to the user. Embodiment 130: A display system as described in embodiment 2, wherein the stimulus includes one or more visual instructions projected to the user. Embodiment 131: The display system described in embodiment 1, further comprising a microphone configured to detect a user's vocalizations. Embodiment 132: A display system as described in embodiment 1, wherein the display system is further configured to assess the user's alertness based, at least in part, on the user's response to the stimulus. Embodiment 133: A display system as described in embodiment 1 or embodiment 16, wherein the neurological disease includes a neurological disease associated with the user's wakefulness. Embodiment 134: A display system as described in embodiment 16, wherein the sensory aid includes visual content selected to increase the user's alertness. Embodiment 135: A display system as described in embodiment 16, wherein the sensory assistance includes modifying visual content and increasing the user's alertness. Embodiment 136: A display system as described in embodiment 1, wherein the display system is further configured to evaluate the user's attention based, at least in part, on the user's response to the stimulus. Embodiment 137: A display system as described in embodiment 1, wherein the stimulus includes instructions for reciting a sequence of words. Embodiment 138: A display system as described in embodiment 137, wherein the display system is further configured to evaluate the user's ability to recite the sequence. Embodiment 139: A display system as described in embodiment 1, wherein the stimulus includes an array of symbols and instructions for identifying one or more of the symbols based on one or more criteria presented to the user. Embodiment 140: A display system as described in embodiment 139, wherein the display system is further configured to determine the accuracy of the user's identification of one or more symbols. Embodiment 141: A display system as described in embodiment 1, wherein the display system is further configured to assess the user's state of orientation based, at least in part, on the user's response to the stimulus. Embodiment 142: A display system as described in embodiment 1, wherein the stimulus includes instructions for stating information, including the user's name. Embodiment 143: A display system as described in embodiment 1, wherein the stimulus includes instructions for stating information, including the user's location. Embodiment 144: A display system as described in embodiment 1, wherein the stimulus includes instructions for stating information, including the current date. Embodiment 145: A display system described in any of embodiments 142-144, wherein the display system is further configured to evaluate the user's orientation state based, at least in part, on the user's ability to accurately state the commanded information. Embodiment 146: A display system as described in embodiment 145, further comprising one or more physiological sensors, wherein the display system is configured to determine whether the user is panicking based, at least in part, on the physiological data. Embodiment 147: A display system as described in embodiment 146, wherein the display system is configured to assess the user's orientation state based, at least in part, on physiological data. Embodiment 148: A display system as described in embodiment 1 or embodiment 16, wherein the neurological disease includes a neurological disease associated with the user's orientation state. Embodiment 149: A display system as described in embodiment 16, wherein the sensory aid includes an audible or visual indication of the user's location. Embodiment 150: A display system as described in embodiment 16, wherein the sensory aid includes an audible or visual indication of time. Embodiment 151: A display system as described in embodiment 16, wherein the sensory aid includes calming audio or visual content in response to determining that the user is panicking. Embodiment 152: A display system as described in embodiment 1, wherein the display system is further configured to evaluate the user's memory ability based, at least in part, on the user's response to the stimuli. Embodiment 153: A display system as described in embodiment 1, wherein the display system is further configured to evaluate the user's learning ability based, at least in part, on the user's response to the stimuli. Embodiment 154: A display system as described in embodiment 1, wherein the stimulus includes information to be memorized by the user. Embodiment 155: A display system as described in embodiment 1, wherein the stimulus includes a step of instructing the user to recall information. Embodiment 156: A display system as described in embodiment 155, wherein the information includes historical data. Embodiment 157: A display system as described in embodiment 1, wherein the stimulus includes a step of presenting information to a user and, after a time delay, instructing the user to recall the information. Embodiment 158: A display system as described in embodiment 157, wherein the time delay is at least 1 minute. Embodiment 159: A display system as described in embodiment 157, wherein the display system is configured to distract the user during the time delay. Embodiment 160: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease is a neurological disease associated with the user's memory. Embodiment 161: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease is a neurological disease associated with the user's learning ability. Embodiment 162: A display system as described in embodiment 16, wherein the sensory aid includes one or more instructions for performing a task. Embodiment 163: A display system as described in embodiment 1, wherein the display system is further configured to evaluate the user's language function based, at least in part, on the user's response to the stimuli. Embodiment 164: A display system as described in embodiment 1, wherein the stimulus includes instructions for speaking on a topic. Embodiment 165: A display system as described in embodiment 164, wherein the display is configured to detect a user's vocalization following an instruction and evaluate the user's spontaneous speech function based on the vocalization. Embodiment 166: A display system as described in embodiment 1, wherein the stimulus includes a photograph of an object and an instruction to state the name of the object. Embodiment 167: A display system as described in embodiment 164, wherein the display system is further configured to determine whether the user has correctly stated the name of the object. Embodiment 168: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease is a neurological disease associated with the user's language function. Embodiment 169: A display system as described in embodiment 16, wherein the sensory assistance includes a step of displaying a word to the user in response to determining that the user is unable to recall the word. Embodiment 170: A display system as described in embodiment 16, wherein the sensory assistance includes notifying the user of detected errors in the user's speech. Embodiment 171: A display system as described in embodiment 1, wherein the stimulus includes a manual agnosia test. Embodiment 172: A display system as described in embodiment 1, wherein the user's reaction includes the user's eye gaze. Embodiment 173: A display system as described in embodiment 1, wherein the user's response includes the amount of time elapsed from the stimulus to the user's response. Embodiment 174: The display system of embodiment 1, wherein the neurological disease comprises Gerstmann's syndrome. Embodiment 175: A display system as described in embodiment 1, wherein the stimulus includes an agraphia test. Embodiment 176: A display system as described in embodiment 175, wherein the agraphia test includes a step of prompting the user to write a word in space. Embodiment 177: A display system as described in embodiment 175, wherein the agraphia test includes a step of prompting the user to write words on a document. Embodiment 178: A display system as described in embodiment 1, wherein the stimulus includes a left-right discrimination impairment test. Embodiment 179: A display system as described in embodiment 178, wherein the left-right discrimination impairment test includes a step of prompting the user to touch a part of the body opposite the finger with the finger. Embodiment 180: A display system as described in embodiment 178, wherein the left-right discrimination impairment test includes a step of prompting the user to identify the direction. Embodiment 181: The display system of embodiment 1, wherein the stimulus comprises a arithmetic test.Embodiment 182: The display system of embodiment 181, wherein the arithmetic test comprises prompting the user to solve an arithmetic problem. Embodiment 183: The display system of embodiment 1, wherein the user's reaction includes a calculation error. Embodiment 184: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease includes dyspraxia. Embodiment 185: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease comprises Huntington's disease. Embodiment 186: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease includes posterior cortical atrophy. Embodiment 187: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease includes aphasia. Embodiment 188: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease includes agnosia. Embodiment 189: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease includes agraphia. Embodiment 190: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease includes dyslexia. Embodiment 191: A display system described in embodiment 1 or embodiment 16, wherein the neurological disease includes dysgraphia. Embodiment 192: The display system of embodiment 1, wherein the stimulus comprises an apraxia test.Embodiment 193: The display system of embodiment 192, wherein the apraxia test comprises prompting the user to imitate a hand gesture. Embodiment 194: A display system as described in embodiment 1, wherein the display device is configured to compare the user's reaction with an overlay of an enhanced normal response. Embodiment 195: A display system as described in embodiment 16, wherein the display system is further configured to monitor the movement of the user's arm, hand, leg, or foot. Embodiment 196: A display system as described in embodiment 16, wherein the stimuli directed to the user are repeated periodically to develop habits, routines, or physical activities in the user. Embodiment 197: A display system as described in embodiment 16, wherein the sensory aid includes a hint to the user of the correct response. Embodiment 198: A display system as described in embodiment 16, wherein the sensory aids provided to the user include visual aids. Embodiment 199: A display system as described in embodiment 198, in which the sensory aids provided to the user include writing techniques. Embodiment 200: A display system as described in embodiment 16, wherein the sensory aid includes a location provided by the display system of a location of a body part prompted by the display system. Embodiment 201: A display system as described in embodiment 16, wherein the sensory aid includes displaying missing steps of an arithmetic solution. Embodiment 202: A display system as described in embodiment 16, wherein the sensory assistance includes identifying correct answers to arithmetic tests. Embodiment 203: A display system as described in embodiment 16, wherein the sensory aid includes an image showing how the task is to be performed. Embodiment 204: A display system as described in embodiment 203, in which the sensory aid includes an image that divides the task into its constituent components. Embodiment 205: A display system as described in embodiment 16, wherein the sensory assistance includes a step of providing an example of correct behavior. Embodiment 206: A display system as described in embodiment 16, wherein the sensory aid includes visual or auditory content to motivate the user to complete a task. Embodiment 207: A display system as described in embodiment 16, wherein the sensory assistance includes language translation. Embodiment 208: A display system as described in embodiment 1, wherein the provided stimulus includes a visuospatial task. Embodiment 209: A display system as described in embodiment 208, wherein the user's response includes an indication of neglect or abnormal structural ability. Embodiment 210: A display system as described in embodiment 209, wherein the neurological disease is associated with right parietal lobe dysfunction. Embodiment 211: A display system as described in embodiment 1, wherein the provided stimulus includes a cognitive task. Embodiment 212: A display system as described in embodiment 211, wherein the user's response includes an indication of abnormal executive function. Embodiment 213: A display system as described in embodiment 212, wherein the neurological disease is associated with frontal lobe dysfunction. Embodiment 214: A display system as described in embodiment 1, wherein the provided stimulus includes a logical or abstraction task. Embodiment 215: A display system as described in embodiment 214, wherein the user's response includes an indication of difficulty in thinking, reasoning, multi-step instruction, or classification. Embodiment 216: A display system as described in embodiment 215, wherein a neurological disease is associated with an area involving higher-order associated cortex. Embodiment 217: A display system as described in embodiment 6, wherein the sensed stimulus includes a visuospatial task. Embodiment 218: A display system as described in embodiment 217, wherein the display system is configured to determine an indication of neglect or abnormal structural ability based, at least in part, on a user's response to a visuospatial task. Embodiment 219: A display system as described in embodiment 218, wherein the neurological disease is associated with right parietal lobe dysfunction. Embodiment 220: A display system as described in embodiment 6, wherein the sensed stimulus includes a cognitive task. Embodiment 221: A display system as described in embodiment 220, wherein the display system is configured to determine an indication of abnormal executive function based, at least in part, on a user's response to a cognitive task. Embodiment 222: A display system as described in embodiment 221, wherein the neurological disease is associated with frontal lobe dysfunction. Embodiment 223: A display system as described in embodiment 6, wherein the sensed stimulus includes a logical or abstraction task. Embodiment 224: A display system as described in embodiment 1, wherein the provided stimulus comprises a light pattern having wavelengths within one or more spectral ranges. Embodiment 225: The display system of embodiment 224, wherein the user's response includes a change in pupil size, and the change in pupil size can vary based on the wavelength in the light pattern.Embodiment 226: The display system of any of embodiments 224-225, wherein the neurological disease is associated with a circadian rhythm abnormality. Embodiment 227: A display system as described in embodiment 69, wherein the user's reaction includes a change in the near-distance convergence point. Embodiment 228: A display system as described in embodiment 227, wherein the neurological disease is associated with a concussion or a subconcussive impact. Embodiment 229: A display system, comprising: 1. A head-mounted display configured to project light onto a user and display augmented reality image content on multiple depth planes, comprising: a display comprising one or more waveguides configured to project light to a user; the one or more waveguides are further configured to transmit light from the ambient environment to a user; The display system may include one or more stimuli that enhance neuroplasticity. configured to provide Display system. Embodiment 230: A display system as described in embodiment 229, wherein one or more stimuli are provided as part of a video game. Embodiment 231: A display system described in either embodiment 229 or 230, wherein the one or more stimuli include electrical signals applied to the user's skull via electrodes connected to the display system. Embodiment 232: A display system as described in embodiment 231, wherein the electrical signals reproduce the brain activity of another individual. Embodiment 233: determining a user's response to the provided stimuli; adjusting the stimulation based on the determined response; A display system described in any of embodiments 229-232, further configured as follows. Embodiment 234: determining a user's response to the provided stimuli; Modifying the determined response, triggering a sensory aid; A display system described in any of embodiments 229-233, further configured as follows: Embodiment 235: A display system, comprising: 1. A head-mounted display configured to project light onto a user and display augmented reality image content on multiple depth planes, comprising: one or more waveguides configured to project light to a user, the one or more waveguides further configured to transmit light from the surrounding environment to the user; a probe that delivers electromagnetic or acoustic energy to a user; and A display system comprising a display comprising: Embodiment 236: A display system as described in embodiment 235, wherein the auxiliary component includes an electrode, an ultrasonic transducer, or an optical source. Embodiment 237: A display system described in any of embodiments 235-236, wherein the probe is configured to deliver electromagnetic or acoustic energy to the user's eye or skull. Embodiment 238: A display system as described in embodiment 237, wherein the auxiliary component is configured to deliver electromagnetic energy configured to penetrate the skull and stimulate a portion of the user's brain. Embodiment 239: A display system described in any of embodiments 237-238, wherein the electromagnetic energy includes wavelengths within at least one of the ultraviolet, non-visible, visible, or infrared spectral ranges. Embodiment 240: A display system described in any of embodiments 237-239, wherein the electromagnetic energy comprises a pulsed optical signal having a frequency of approximately 1 to 50 Hz. Embodiment 241: A display system as described in embodiment 247, wherein the acoustic energy includes an ultrasound signal to the user's skull. Embodiment 242: A display system as described in embodiment 241, wherein the display system is configured to acquire images of blood flow through the middle cerebral artery. Embodiment 243: A display system described in any of embodiments 235-242, wherein the probe is configured to generate a collimated laser beam that illuminates a structure in the user's eye and generates a speckle pattern, and the display system is configured to detect the speckle pattern and correlate a parameter associated with the speckle pattern with the blood flow rate in the ocular tissue. Embodiment 244: A display system as described in embodiment 243, wherein the parameter associated with the speckle pattern is normalized blur. Embodiment 245: A display system, comprising: 1. A head-mounted display configured to project light onto a user and display augmented reality image content on multiple depth planes, comprising: a display comprising one or more waveguides configured to project light to a user; the one or more waveguides are further configured to transmit light from the ambient environment to a user; the display system is configured to track eye movements and determine a neurological disorder associated with one or more abnormalities in the tracked eye movements; the display system is configured to provide one or more stimuli to inhibit one or more abnormalities in the tracked eye movements or to retrain one or more portions of the brain responsible for an associated neurological disorder; Display system. Embodiment 246: A display system as described in embodiment 245, wherein the tracked eye movement includes pupil movement due to nystagmus, and one or more stimuli include images that are moved by an amount less than the amplitude of the nystagmus eye movement. Embodiment 247: A display system, comprising: 1. A head-mounted display configured to project light onto a user and display augmented reality image content on multiple depth planes, comprising: a display comprising one or more waveguides configured to project light to a user; the one or more waveguides are further configured to transmit light from the ambient environment to a user; The transmitted light is used to examine the fundus of the user, The display system is configured to determine a neurological disease based on an examination of the fundus. Display system. Embodiment 248: The display system described in embodiment 247, wherein the neurological disease includes at least one of intrascalp pressure, increased intrascalp pressure, compressive optic neuropathy, arteritic ischemic optic neuropathy, non-arteritic ischemic optic neuropathy, optic neuritis, or radiation optic neuropathy. Embodiment 249: A display system as described in embodiment 69, wherein the user's response includes an inability to fixate on the object for a predetermined time interval. Embodiment 250: A display system as described in embodiment 249, wherein the neurological disease is associated with autism, attention deficit hyperactivity disorder, or Parkinson's disease. Embodiment 251: A display system as described in embodiment 116, wherein the sensory assistance includes visual sensory deprivation. Embodiment 252: A display system as described in embodiment 116, wherein the sensory assistance includes a step of displaying a uniform color field to the user. Embodiment 253: A display system as described in embodiment 116, wherein the sensory assistance includes noise canceling. Embodiment 254: A display system as described in embodiment 116, wherein the sensory assistance includes auditory and visual sensory deprivation. Embodiment 255: The display system of embodiment 1, wherein the display system is configured to map blood flow in the user's brain using functional near-infrared spectroscopy.Embodiment 256: The display system of embodiment 11, wherein the display system is configured to map blood flow in the user's brain using functional near-infrared spectroscopy. Embodiment 257: A display system, comprising: a head-mountable augmented reality display configured to output light with a variable wavefront divergence and display virtual content; one or more inwardly directed sensors; one or more outwardly directed sensors; one or more processors; When executed by one or more processors, the one or more processors determining a response to the stimulus by receiving data from one or more inwardly directed sensors; Identifying neurological disorders associated with the reaction; performing a neurological analysis by determining an environmental trigger associated with a neurological disorder; monitoring the surrounding environment with one or more outwardly directed sensors; detecting the presence of an environmental trigger in the surrounding environment; providing a sensory aid based on the detected presence of the trigger variable; one or more computer storage media for storing instructions for performing operations, including: A display system comprising: Embodiment 258: A display system as described in embodiment 257, wherein the step of providing sensory assistance includes a step of displaying virtual content. Embodiment 259: A display system as described in embodiment 258, wherein the neurological disease includes memory loss and the sensory assistance includes one or more of a reminder and an alert. Embodiment 260: A display system as described in embodiment 258, wherein the step of providing sensory assistance includes a step of modifying the perceived color of a real object. Embodiment 261: A display system as described in embodiment 257, wherein the sensory assistance includes a sound associated with an environmental trigger. Embodiment 262: A display system as described in embodiment 257, wherein the neurological analysis is performed automatically multiple times over several months, and further includes a step of updating the user's neurological profile based on the neurological analysis. Embodiment 263: A display system as described in embodiment 257, wherein the display comprises a waveguide comprising a diffractive optical element configured to output light by extracting light from the waveguide, the waveguide being one of a stack of waveguides, each of the stack waveguides being configured to output light with a different wavefront divergence. Embodiment 264: A display system, comprising: a head-mountable augmented reality display configured to output light with a variable wavefront divergence and display virtual content; one or more inwardly directed sensors; one or more processors; When executed by one or more processors, the one or more processors determining a response to the stimulus by receiving data from one or more inwardly directed sensors; Identifying neurological disorders associated with the reaction; performing a neurological analysis by and one or more computer storage media for storing instructions for performing operations on the display system. Embodiment 265: A display system as described in embodiment 264, wherein the operation further includes a step of causing the display system to display a sensory aid. Embodiment 266: The display system of embodiment 265, wherein the sensory aid is selected based on one or more of the identified neurological diseases and reactions.Embodiment 267: The display system of embodiment 265, wherein the sensory aid is selected based on a user profile. Embodiment 268: A display system as described in embodiment 264, wherein performing the neurological analysis includes a step of providing a stimulus, the stimulus including virtual content output by the display. Embodiment 269: A display system as described in embodiment 264, wherein the stimulus includes a virtual object that is moved from a far depth plane to a near depth plane. Embodiment 270: A display system as described in embodiment 264, wherein the neurological disease is at least one of a visual processing disorder and a memory disorder. Embodiment 271: A display system as described in embodiment 264, wherein the stimulus is a stimulus present in the surrounding environment. Embodiment 272: A display system as described in embodiment 264, wherein the step of identifying a neurological disease includes a step of generating a list of potential neurological diseases. Embodiment 273: The operation further comprises: automatically repeating the neurological analysis multiple times over several months; A display system as described in embodiment 264, wherein the step of repeating the neurological analysis includes a step of updating the identified neurological disease. Embodiment 274: A display system as described in embodiment 264, wherein the operation further includes a step of transmitting the identified neurological disease to a plurality of other display systems. Embodiment 275: A display system as described in embodiment 274, wherein the operation includes identifying a neurological disease based on criteria determined from a population of users of other display systems. Embodiment 276: A display system as described in embodiment 264, wherein the display is configured to output virtual content with an accommodation-vergence-divergence movement mismatch of less than 0.25 diopters. Embodiment 277: A display system as described in embodiment 264, wherein the one or more inwardly directed sensors comprise electrodes configured to measure an electrical potential. Embodiment 278: A method implemented by a display system comprising one or more processors, one or more inwardly directed sensors, and a head-mounted display, determining a user response to the stimulus by collecting data from one or more inwardly directed sensors; Identifying neurological disorders associated with the reaction; The method includes a step of performing a neurological analysis by Embodiment 279: The method described in embodiment 278, further comprising the step of displaying a sensory aid. Embodiment 280: The method described in embodiment 278, wherein the sensory assistance is based on an identified neurological disease, response, or user profile. Embodiment 281: The method described in embodiment 278, further comprising the step of automatically repeating the neurological analysis multiple times over several months and updating the identified neurological diseases. The present invention provides, for example, the following. (Item 1) 1. A display system comprising: a head-mountable augmented reality display configured to output light with a variable wavefront divergence and display virtual content; one or more inwardly directed sensors; one or more outwardly directed sensors; one or more processors; One or more computer storage media having instructions stored thereon that, when executed by the one or more processors, cause the one or more processors to: conducting a neurological analysis, said conducting said neurological analysis comprising: determining a response to the stimulus by receiving data from the one or more inwardly directed sensors; identifying a neurological disorder associated with said response; and determining an environmental trigger associated with the neurological disorder; monitoring an ambient environment with the one or more outwardly directed sensors; detecting the presence of an environmental trigger within the ambient environment; providing a sensory aid based on the detected presence of the environmental trigger; one or more computer storage media for performing operations including A display system comprising: (Item 2) Item 10. The display system of item 1, wherein providing the sensory aid includes displaying virtual content. (Item 3) Item 3. The display system of item 2, wherein the neurological condition includes memory loss and the sensory aids include one or more of a reminder and an alert. (Item 4) 3. The display system of claim 2, wherein providing the sensory aid comprises modifying the perceived color of a real object. (Item 5) Item 10. The display system of item 1, wherein the sensory aid includes a sound associated with the environmental trigger. (Item 6) Item 10. The display system of item 1, wherein the neurological analysis is performed automatically multiple times over several months, and further comprising updating the user's neurological profile based on the neurological analysis. (Item 7) Item 1, a display system according to item 1, wherein the display comprises a waveguide comprising a diffractive optical element configured to output light by extracting the light from the waveguide, the waveguide being one of a stack of waveguides, each of the stack waveguides being configured to output light with a different wavefront divergence. (Item 8) 1. A display system comprising: a head-mountable augmented reality display configured to output light with a variable wavefront divergence and display virtual content; one or more inwardly directed sensors; one or more processors; One or more computer storage media having instructions stored thereon that, when executed by the one or more processors, cause the one or more processors to: conducting a neurological analysis, said conducting said neurological analysis comprising: determining a response to the stimulus by receiving data from the one or more inwardly directed sensors; identifying a neurological disorder associated with said response; To be carried out by one or more computer storage media for performing operations including A display system comprising: (Item 9) Item 9. The display system of item 8, wherein the operations further include causing the display system to display a sensory aid. (Item 10) 10. The display system of claim 9, wherein the sensory aid is selected based on one or more of the identified neurological disorder and the response. (Item 11) 10. The display system of claim 9, wherein the sensory aids are selected based on a user profile. (Item 12) 9. The display system of claim 8, wherein performing the neurological analysis includes providing the stimulus, the stimulus including virtual content output by the display. (Item 13) Item 9. The display system of item 8, wherein the stimulus includes a virtual object that is moved from a far depth plane to a near depth plane. (Item 14) 9. The display system of claim 8, wherein the neurological disease is at least one of a visual processing disorder and a memory disorder. (Item 15) 9. The display system of claim 8, wherein the stimulus is a stimulus present in the surrounding environment. (Item 16) 9. The display system of claim 8, wherein identifying the neurological disease includes generating a list of potential neurological diseases. (Item 17) The operation further comprises: automatically repeating said neurological analysis multiple times over several months; Including, 9. The display system of claim 8, wherein repeating the neurological analysis includes updating the identified neurological disease. (Item 18) Item 9. The display system of item 8, wherein the operations further include transmitting the identified neurological disease to a plurality of other display systems. (Item 19) Item 19. The display system of item 18, wherein the operation includes identifying the neurological disease based on criteria determined from a population of users of the other display system. (Item 20) Item 9. The display system of item 8, wherein the display is configured to output virtual content with an accommodation-vergence-divergence mismatch of less than 0.25 diopters. (Item 21) Item 9. The display system of item 8, wherein the one or more inwardly directed sensors comprise electrodes configured to measure an electrical potential. (Item 22) 1. A method implemented by a display system comprising one or more processors, one or more inwardly directed sensors, and a head-mounted display, the method comprising: conducting a neurological analysis, said conducting said neurological analysis comprising: determining a user response to the stimulus by collecting data from the one or more inwardly directed sensors; identifying a neurological disorder associated with said response; To be carried out by A method comprising: (Item 23) 23. The method of claim 22, further comprising displaying a sensory aid. (Item 24) 23. The method of claim 22, wherein the sensory aid is based on the identified neurological disorder, the response, or a user profile. (Item 25) 23. The method of claim 22, further comprising automatically repeating the neurological analysis multiple times over several months and updating the identified neurological disorders. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 illustrates a user's view of an augmented reality (AR) device.

[0012] [Figure 2] FIG. 2 illustrates a conventional display system for simulating a three-dimensional image for a user.

[0013] [Figure 3] 3A-3C illustrate the relationship between the radius of curvature and the radius of focus.

[0014] [Figure 4A] Figure 4A illustrates the representation of the accommodation-vergence-divergence motor response of the human visual system.

[0015] [Figure 4B] FIG. 4B illustrates an example of different accommodation and convergence states of a pair of a user's eyes.

[0016] [Figure 4C] FIG. 4C illustrates an example of a top-down view representation of a user viewing content through a display system.

[0017] [Figure 4D] FIG. 4D illustrates another example of a top-down view representation of a user viewing content through a display system.

[0018] [Figure 5] FIG. 5 illustrates aspects of an approach for simulating three-dimensional images by correcting for wavefront divergence.

[0019] [Figure 6] FIG. 6 illustrates an embodiment of a waveguide stack for outputting image information to a user.

[0020] [Figure 7] FIG. 7 illustrates an example of an output beam output by a waveguide.

[0021] [Figure 8] FIG. 8 illustrates an example of a stacked waveguide assembly where each depth plane contains an image formed using multiple different primary colors.

[0022] [Figure 9A] FIG. 9A illustrates a cross-sectional side view of an example of a set of stacked waveguides, each including an internal coupling optical element.

[0023] [Figure 9B] FIG. 9B illustrates a perspective view of the multiple stacked waveguide embodiment of FIG. 9A.

[0024] [Figure 9C] FIG. 9C illustrates a top-down plan view of the multiple stacked waveguide embodiment of FIGS. 9A and 9B.

[0025] [Figure 9D] FIG. 9D illustrates an example of a wearable display system.

[0026] [Figure 10] FIG. 10 shows a schematic diagram of an example of various components of an augmented reality system, including environmental and user sensors.

[0027] [Figure 11] FIG. 11 illustrates an example of a method for determining the presence of a neurological disease using a display system.

[0028] [Figure 12] FIG. 12 is a flow chart illustrating an example of a method for displaying sensory aids to a user in response to a neurological disorder of the user.

[0029] The drawings are provided to illustrate example embodiments and are not intended to limit the scope of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0030] Many individuals have neurological disorders, including visual processing disorders, that undesirably interfere with their lives. Such neurological disorders may be abnormalities or defects within an individual's visual processing pathways and / or nervous system, including abnormalities within the individual's brain. For example, an individual may be unable to see objects in a certain location. As another example, an individual may have a memory deficit, which may increase in prevalence as the individual ages. As yet another example, an individual may have a neuromuscular disorder that interferes with normal oculomotor function.

[0031] Advantageously, in some embodiments, the augmented reality (AR) display systems disclosed herein may be configured to determine the presence of neurological disorders, including visual processing abnormalities. Further, the AR display systems may be configured to address and / or modify neurological disorders, including brain information processing.

[0032] It should be understood that an AR system may display virtual content to a user or viewer while still allowing the user to see the world around them. Preferably, this content is displayed on a head-mounted display that projects image information to the user's eyes, for example, as part of eyewear. In addition, the display may also transmit light from the surrounding environment to the user's eyes, providing a view of the surrounding environment. As used herein, it should be understood that a "head-mounted" or "head-mountable" display is a display that can be mounted on the viewer's head.

[0033] As discussed further below, many VR, AR, and MR display devices suffer from accommodation-vergence mismatch when displaying image information. Such mismatch can cause discomfort to the user and make long-term wear of the device impractical. Advantageously, display devices according to embodiments herein enable long-term wear of the device by, among other things, providing a correct match between accommodation and vergence in the user. For example, images displayed to a viewer may have an accommodation-vergence mismatch of about 0.5 diopters or less, about 0.33 diopters or less, or about 0.25 diopters or less, in some embodiments, including about 0.1 diopters or less. As a result, a user of the device may be able to wear and use the device substantially continuously for a duration of 3 or more hours, 4 or more hours, 5 or more hours, 6 or more hours, or an entire day without removing the device for more than 25%, more than 20%, more than 15%, more than 10%, or more than 5% of the time. In some embodiments, the display device may display the augmented reality image substantially continuously for the aforementioned durations.

[0034] The wearability and long-term nature of the wearability of the display systems disclosed herein, combined with the proximity of the display system to the user, including sensor-based components, advantageously facilitate various neurological assessments and treatments. As discussed herein, the sensor-based components may include inwardly directed sensors configured to sense parameters related to the user and outwardly directed sensors configured to detect parameters related to the ambient environment around the user. In some embodiments, the display system may be configured to use the outwardly directed sensors to actively monitor the user's environment and provide corrective aids, e.g., sensory aids, to help the user address deficiencies in their ability to perceive and / or interact with the world. For example, the display system may monitor the ambient environment for the presence of environmental triggers associated with neurological disorders. When an environmental trigger is detected, the display system provides sensory aids based on the detected environmental trigger. For users with memory deficiencies, the display system may be configured to monitor external variables, such as time, and provide reminders to take certain actions (e.g., take medication, see a healthcare provider, etc.). In addition to helping users accomplish individual tasks, the display system, due to its ability to be worn long-term (e.g., daily for a large portion of the day), may enable consistent routines to be established, thereby further promoting the user's ability to function independently of others.

[0035] In some embodiments, the display system may be configured to present conclusions regarding the presence of various neurological disorders (e.g., abnormalities) in the user. For example, the display system may be configured to provide stimuli, e.g., pre-selected content, to the user and measure the user's response to the content, e.g., using inwardly directed sensors. The stimuli may take the form of visual and / or auditory content. Additionally or alternatively, the stimuli may be provided by the surrounding environment. For example, scenes (including scenery, people, and other visual features) or sounds not generated by the display system but experienced by the user may be detected and categorized by the display system. If the system determines that an environmental visual or auditory stimulus is of an appropriate type for a particular neurological test, the display system may also measure the user's response to the stimuli, effectively conducting that neurological test. Thus, as used herein, stimuli provided by the display system may be generated by the display system and directed to the user, or may be present in the surrounding environment and registered and identified by the display system. Known variables of the provided content and the user's response may be analyzed to determine the presence of a neurological disorder, such as an abnormality in visual processing. It should be understood that the display system may display visual content for each eye and may vary various visual parameters, including the location of the visual content, the depth plane at which the content is displayed, the duration of exposure to the visual content, etc. By varying the visual content and these visual parameters, different analyses may be performed as described herein.

[0036] Such analysis may be performed solely for diagnostic, therapeutic, and / or monitoring purposes, e.g., to assist the user and / or clinician in monitoring the user's health. Preferably, conclusions derived from the analysis are stored in the display system and / or a remote database accessible to the display system, and the conclusions may subsequently be utilized to determine whether a particular sensory aid (e.g., a corrective aid) should be applied. In various embodiments, conclusions derived from the analysis may also be used to monitor the effectiveness of the applied sensory aid. For example, the user may be retested for a disease to determine the effectiveness of a sensory aid applied to address the disease.

[0037] In some embodiments, the sensory aid may be a mental exercise or activity to modify the user's brain's processing of information. For example, the display system may be configured to function as a learning aid, and various "brain exercises" may be provided by the display system. In some embodiments, these brain exercises may be provided manually in response to a user's selection, or the user may be automatically given the option to perform a brain exercise based on biofeedback, prescriptions, and / or results of a neurological analysis. In some embodiments, the implementation and provision of the option to perform a brain exercise may be triggered by an external stimulus sensed by the display system and / or by a user input instructing the display system to perform a brain exercise. For example, an activity such as a game to improve memory may be presented to the user in response to the detection of a memory impairment and then adjusted manually or automatically through biofeedback.

[0038] Advantageously, the display system's long-term wearability (e.g., due to its ability to provide correct accommodation-vergence-divergence alignment) provides a platform that allows for long-term neurological analyses to be performed and also allows for the real-time selective provision of corrective or learning aids as needed (e.g., due to the identification of a disorder requiring such corrective aids and / or by sensing the presence of a stimulus in the environment that necessitates such aids). Furthermore, these benefits may be achieved without requiring the user to visit a medical facility and perform various analyses. Rather, analyses may be performed periodically or at arbitrary times, for example, when triggered by a specific stimulus, when selected by the user, based on a prescription, etc. This flexibility and ubiquity allow the user to perform periodic diagnostics and update corrective aids as needed. It should be understood that the determinations and conclusions made by the system are based on available inputs and current programming, and these conclusions are not necessarily correct. As discussed herein, accuracy may be improved over time in some embodiments by repeatedly performing analyses.

[0039] Without being limited by theory, some researchers believe that the effectiveness of retraining and / or modifying (rewiring) the neural tissue of the brain can be improved by long-term and / or repeated exposure to stimuli and learning plans. Thus, due at least in part to the wearability of the display system, users can wear the display system for longer periods of time and more frequently, thereby increasing the number of repetitions and duration over which retraining exercises can be applied. Furthermore, various retraining exercises can be performed at arbitrary times throughout the day and in a variety of different environments (e.g., whenever the user has "free time"), thereby further increasing the number of repetitions that can be performed. As a result, the effectiveness and efficacy of the retraining exercises can be increased.

[0040] Additionally, the display system may allow a user to track their health over time and determine their progress as they undergo a treatment plan, e.g., mental exercises. It should be appreciated that such active monitoring and feedback to the user can increase the likelihood that the user will continue with a particular treatment plan, especially if the feedback provides positive reinforcement and an indication of progress. Because the display device may be worn daily, the frequency of tracking various ailments and / or abilities to provide feedback to the user over an extended period of the day is increased, which may increase the effectiveness of the treatment plan.

[0041] It should also be appreciated that the display system may provide advantages for increasing the accuracy of diagnosis of various neurological disorders. For example, the display system may be configured to allow for the collection of data sets that could not otherwise be easily obtained. Because the display system may preferably be worn for extended periods of time while the user moves around during part or all of their daily life, the number and / or repetition of various analyses may be higher than those obtained if the user were required to visit a clinician's office (although the system may also be advantageously applied in a clinician's office setting). Furthermore, various analyses may also be linked to data that cannot be detected within a clinician's office. For example, the environment in which the analysis is performed (including, for example, the presence of pollutants, etc.), the time of day, the time of year, etc. may be linked to the measured user response. As a result, among other things, the duration of data collection, the variety of data, the variety of locations of data collection, and the ability to collect multiple types of data simultaneously (thereby allowing different data to be cross-referenced, for example, using timestamps and / or location stamps applied to all of the data) may increase the accuracy of any analysis performed on the user and may reveal relationships between health conditions or treatments and various measured variables that would not otherwise be readily apparent. Additionally, the ability to wear the display device for extended periods of time can enable fine automatic adjustments based on biofeedback, signal noise filtering of recurring and / or predictive artifacts, or direct user interaction to identify adverse or favorable display system performance conditions. It should be understood that the display system may include various sensors, such as electrodes and sensors for detecting gaze and head pose. In some embodiments, signal noise filtering of recurring and / or predictive artifacts may be aided by data from gaze tracking and / or head pose cameras, electrodes (e.g., EEG), or other data sources. Signals may be denoised after collection and before further processing.In some embodiments, the system may discard data and / or filter data to enhance or improve the signal based on the detected movements of the user.

[0042] It should be understood that the display system may collect and have access to information about a person over time. This provides a more complete profile of the user, including environmental stimuli to which the user may be exposed. This profile provides additional inputs and criteria that can be considered to assess conclusions for analysis and the likelihood of a particular conclusion. Additionally, by allowing tests to be performed by the user at will and / or regularly scheduled times, the display system may increase the number of tests performed, thereby increasing the data set, which may be expected to increase the accuracy of the tests. For example, the display system may be configured to filter out or ignore outlying data points. Conversely, the display system can be programmed to perform tests at arbitrary and different times, seeking the best conditions for user engagement, signal acquisition performance, and system noise or artifact minimization. In some embodiments, because the user preferably wears the display system daily, the display system may be configured to automatically perform various tests periodically over a period of weeks, months, or years as the user wears the device over that period.

[0043] Advantageously, the display system allows multiple of the analyses disclosed herein to be performed simultaneously or sequentially.The ability to perform multiple tests for a given visual processing pathway or disease can also increase the accuracy of any conclusions drawn from those tests.The various analyses disclosed herein can be evaluated over time, for example, with respect to the variability between people (inter-individual variability) and within a given person (intra-individual variability).

[0044] In some embodiments, information may be shared between different users of display systems configured to perform the analyses disclosed herein. For example, information may be transmitted directly between display systems (e.g., via wired and / or wireless connections) and / or via a central server that receives information from display systems and distributes information from other display systems to a given display system. In some embodiments, the display systems may share information regarding the type of stimuli applied, the user's response to the stimuli, and the conclusions drawn from the analysis. In some embodiments, the display systems may also share visual data, such as the user's view (e.g., similar to "screen sharing"), so that a physician can view the user's perspective while the user is undergoing the analysis. In some embodiments, the display systems may also be configured to share other information related to other parameters (preferably parameters that do not specifically identify the user) that may affect the user's health or physiological condition, including location, age, gender, ethnicity, etc. It should be understood that many of the analyses herein rely on comparison to a norm to draw a conclusion about the presence of a neurological disorder (e.g., by determining that an abnormality exists). It should also be understood that norms within a subset of the general population may differ, and the amount of this difference may vary depending, among other things, on the subset being analyzed and / or the inclusion or exclusion of inputs from neurological disorders and peripheral activity sensing or extenuating environmental factors. Advantageously, as noted above, the data set used in the analysis for a particular user may be made more accurate due to the ability to perform multiple tests using the display system. Additionally, the ability to share information between users may further increase the accuracy of any conclusions drawn by analyzing more accurate data sets from individual users and by having a larger data set from the population of users. As a result, norms between the general population of users and specific subsets of users may be compiled.Sharing information among multiple display system users can enable increased study design sophistication, such as the inclusion of control groups and double-blind, placebo-type studies. The display system, which may be connected to a remote processing unit, may be configured to draw comparisons of differences between a specific subset of users and a norm in the general population. Such comparisons may be utilized to determine whether the norm to which a specific user's results are compared can serve as a norm for the general population or a norm for the specific subset of users. As a result, more meaningful comparisons can be made, and more accurate or nuanced conclusions can be drawn from these comparisons by the display system.

[0045] It should be appreciated that in addition to providing an improved basis for comparison, sharing other information about the user may also improve the accuracy of conclusions drawn from the analysis by allowing additional variables to be considered. For example, a certain combination of stimulus and response may be associated with multiple conclusions (e.g., may indicate multiple processing defects). The display system may be configured to access a database, which may be part of the display system and / or may be in a remote database accessible by the display system to obtain information regarding conclusions drawn from testing of other users. This information may include data regarding conclusions associated with one or more of other variables, such as user location, age, ethnicity, activity, interaction, etc. Such information may be cross-referenced with the user's measured responses to help determine the most likely correct conclusion or to rank possible conclusions.

[0046] In some embodiments, the display system's ability to display images at multiple depth planes may be advantageously applied to determine which image of multiple images a viewer is sensing or responding to, without requiring direct user input or complex external instrumentation for measuring brain activity. For example, images to be evaluated may be displayed at different depth planes, and the user's eye accommodation and / or convergence may be measured (e.g., using an eye-tracking camera on the display device). It should be understood that images at different depth planes perceived by the viewer will cause the eyes to assume different accommodation and / or convergence states. As a result, the image perceived by the user may be inferred by 1) determining the user's eye accommodation and / or convergence state and 2) matching that accommodation and / or convergence state with the displayed image or depth plane of the image. The image corresponding to the user's measured accommodation and / or convergence state is then interpreted as the image perceived by the user. In some embodiments, images may be displayed on widely different depth planes (e.g., infinity and the nearest depth plane output by the display system) to increase the expected difference in accommodation and / or vergence state between the images. In some embodiments, the duration for which a user fixates an image (e.g., the amount of time the user's eyes are in a particular accommodation and / or vergence state) may also be measured to infer whether the user is actively perceiving a particular image or whether the change in accommodation and / or vergence state is the result of an involuntary reflex, such as a microsaccade. In various embodiments, the display system may also be used to measure microsaccade amplitude while the user is engaged in fixating the displayed image. It should be understood that such a scheme for detecting user perception may be utilized for a variety of perceptual tests, including, but not limited to, tests related to rivalry, dominance and / or inhibition, backward masking, and forward masking.

[0047] Reference is now made to the drawings, wherein like reference numerals refer to like parts throughout.

[0048] FIG. 2 illustrates a conventional display system for simulating a three-dimensional image for a user. It should be understood that when a user's eyes are spaced apart and view a real object in space, each eye may have a slightly different view of the object, forming an image of the object at a different location on each eye's retina. This may be referred to as binocular disparity and may be utilized by the human visual system to provide the perception of depth. Conventional display systems simulate binocular disparity by presenting two distinct images 190, 200, one for each eye 210, 220, with slightly different views of the same virtual object, corresponding to the view of the virtual object as it would appear by each eye as if it were a real object at a desired depth. These images provide binocular cues that the user's visual system may interpret to derive the perception of depth.

[0049] Continuing with reference to FIG. 2 , images 190 and 200 are spaced apart from eyes 210 and 220 by a distance 230 on the z-axis. The z-axis is parallel to the optical axis of a viewer fixating on an object at optical infinity directly in front of the viewer. Images 190 and 200 are flat and at a fixed distance from eyes 210 and 220. Based on slightly different views of the virtual object in the images presented to eyes 210 and 220, respectively, the eyes may necessarily rotate so that the image of the object falls on corresponding points on the respective retinas of the eyes, maintaining single binocular vision. This rotation may cause the gaze of each eye 210 and 220 to converge on a point in space where the virtual object is perceived to reside. As a result, providing three-dimensional images traditionally involves manipulating the convergence and divergence of the user's eyes 210 and 220 and providing binocular cues that the human visual system interprets to provide the perception of depth.

[0050] However, creating a realistic and comfortable perception of depth is challenging. It should be understood that light from an object at different distances from the eye has a wavefront with different amounts of divergence. Figures 3A-3C illustrate the relationship between distance and light ray divergence. The distance between the object and the eye 210 is represented in order of decreasing distances R1, R2, and R3. As shown in Figures 3A-3C, light rays become more divergent as the distance to the object decreases. Conversely, as the distance increases, the light rays become more collimated. In other words, the light field generated by a point (an object or portion of an object) can be said to have a spherical wavefront curvature that is a function of the distance the point is from the user's eye. As the curvature increases, the distance between the object and the eye 210 decreases. While only a single eye 210 is illustrated in Figures 3A-3C and various other figures herein for clarity of illustration, the discussion regarding the eye 210 may apply to both eyes 210 and 220 of the viewer.

[0051] Continuing with reference to Figures 3A-3C, light from an object at which a viewer's eye is fixating may have different wavefront divergences. Due to the different wavefront divergences, the light may be focused differently by the eye's lens, which in turn may require the lens to assume a different shape to form a focused image on the eye's retina. If a focused image is not formed on the retina, the resulting retinal blur acts as an accommodative cue, causing the shape of the eye's lens to change until a focused image is formed on the retina. For example, the accommodative cue may trigger relaxation or contraction of the ciliary muscles surrounding the eye's lens, thereby modulating the force applied to the suspensory ligaments that hold the lens, thus changing the shape of the eye's lens and forming a focused image of the fixated object on the eye's (e.g., foveal) retina until retinal blur of the fixated object is eliminated or minimized. The process by which the eye's lens changes shape can be referred to as accommodation, and the shape of the eye's lens required to form a focused image of a fixated object on the eye's (e.g., foveal) retina can be referred to as the state of accommodation.

[0052] Referring now to Figure 4A, a representation of the accommodation-vergence response of the human visual system is illustrated. Eye movement to fixate an object causes the eye to receive light from the object, which forms an image on each of the eye's retinas. The presence of retinal blur in the image formed on the retina can provide a cue for accommodation, and the relative location of the image on the retina can provide a cue for vergence. Accommodative cues cause accommodation, resulting in the eye's lens adopting a specific accommodation state in which a focused image of the object is formed on the retina (e.g., the fovea). Conversely, vergence cues cause vergence movements (eye rotations) so that the images formed on each retina of each eye are at corresponding retinal points, maintaining single binocular vision. In these positions, the eyes can be said to adopt a specific vergence state. Continuing with reference to FIG. 4A , accommodation can be understood as the process by which the eyes achieve a particular accommodation state, and convergence can be understood as the process by which the eyes achieve a particular convergence state. As shown in FIG. 4A , the accommodation and convergence states of the eyes can change when the user fixates on a different object. For example, the accommodated state can change when the user fixates on a new object at a different depth on the z-axis.

[0053] Without being limited by theory, it is believed that a viewer of an object may perceive the object as "three-dimensional" due to a combination of convergence and accommodation. As previously mentioned, vergence movement of the two eyes relative to one another (e.g., eye rotation such that the pupils move toward or away from one another, converge the eyes' lines of sight, and fixate on an object) is closely linked to accommodation of the eye's lenses. Under normal conditions, changing the shape of the eye's lenses and shifting focus from one object to another at a different distance will automatically produce a corresponding change in vergence to the same distance, a relationship known as the "accommodation-vergence reflex." Similarly, a change in vergence will trigger a corresponding change in lens shape under normal conditions.

[0054] 4B, an example of different accommodation and convergence states of the eyes is illustrated. Paired eye 222a fixates an object at optical infinity, while paired eye 222b fixates an object 221 at less than optical infinity. Notably, the convergence states of each pair of eyes are different: paired eye 222a points straight ahead, while paired eye 222 converges on object 221. The accommodation states of the eyes forming each pair of eyes 222a and 222b are also different, as represented by the different shapes of lenses 210a, 220a.

[0055] Unfortunately, many users of conventional "3-D" display systems may find such systems uncomfortable or may not perceive any depth perception due to a mismatch between accommodation and convergence states in these displays. As previously mentioned, many stereoscopic or "3-D" display systems display a scene by providing a slightly different image to each eye. Such systems are uncomfortable for many viewers because, among other things, they simply provide different presentations of a scene, causing changes in the eyes' convergence states without corresponding changes in the eyes' accommodation states. Rather, images are presented by the displays at a fixed distance from the eyes so that the eyes view all image information in a single accommodation state. Such an arrangement counters the "accommodation-vergence-divergence reflex" by causing changes in the convergence states without a corresponding change in the accommodation state. This mismatch is believed to cause discomfort to the viewer. Display systems that offer better alignment between accommodation and convergence-divergence movements may create a more realistic and comfortable simulation of three-dimensional images.

[0056] Without being limited by theory, it is believed that the human eye can typically interpret a finite number of depth planes to provide depth perception. As a result, a highly realistic simulation of perceived depth can be achieved by providing the eye with different presentations of images corresponding to each of these limited number of depth planes. In some embodiments, the different presentations may provide both vergence cues and matching cues for accommodation, thereby providing physiologically correct accommodation-vergence divergence matching.

[0057] 4B , two depth planes 240 are illustrated, corresponding to different distances in space from the eyes 210, 220. For a given depth plane 240, vergence-divergence cues may be provided by displaying appropriately different perspective images for each eye 210, 220. Additionally, for a given depth plane 240, the light forming the image provided to each eye 210, 220 may have a wavefront divergence corresponding to the light field generated by a point at the distance of that depth plane 240.

[0058] In the illustrated embodiment, the distance along the z-axis of depth plane 240 containing point 221 is 1 m. As used herein, distance or depth along the z-axis may be measured with a zero point located at the exit pupil of the user's eye. Thus, depth plane 240 located at a depth of 1 m corresponds to a distance of 1 m away from the exit pupil of the user's eye on the optical axis of the eye with the eye pointed toward optical infinity. As an approximation, the depth or distance along the z-axis may be measured from a display (e.g., the surface of a waveguide) in front of the user's eye, and a value for the distance between the device and the exit pupil of the user's eye may be added. That value may be referred to as pupil distance and may correspond to the distance between the exit pupil of the user's eye and a display worn by the user in front of the eye. In practice, the value for pupil distance may be a normalized value generally used for all viewers. For example, pupil distance may be assumed to be 20 mm, and the depth plane at a depth of 1 m may be at a distance of 980 mm in front of the display.

[0059] 4C and 4D, examples of matched accommodation-vergence-divergence distances and mismatched accommodation-vergence-divergence distances are illustrated, respectively. As illustrated in FIG. 4C, the display system may provide an image of a virtual object to each eye 210, 220. The image may cause the eyes 210, 220 to assume a convergence-divergence state in which the eyes converge onto point 15 on the depth plane 240. In addition, the image may be formed by light having a wavefront curvature corresponding to the real object on that depth plane 240. As a result, the eyes 210, 220 assume an accommodation state in which the image is focused on the retinas of those eyes. Thus, the user may perceive the virtual object as being at point 15 on the depth plane 240.

[0060] It should be understood that the accommodation and convergence states of the eyes 210, 220 are each associated with a particular distance on the z-axis. For example, an object at a particular distance from the eyes 210, 220 will cause those eyes to assume a particular accommodation state based on the distance of the object. The distance associated with a particular accommodation state is referred to as the accommodation distance A. d Similarly, a particular convergence-divergence distance V associated with the eyes in a particular convergence-divergence state can be d Or, there exists a position relative to each other. When the accommodation distance and the convergence distance are matched, the relationship between accommodation and convergence is said to be physiologically correct. This is considered to be the most comfortable scenario for the viewer.

[0061] However, in a stereoscopic display, the accommodation distance and the vergence distance may not always be aligned. For example, as illustrated in FIG. 4D , images displayed to the eyes 210, 220 may be displayed with a wavefront divergence corresponding to the depth plane 240, and the eyes 210, 220 may be in a particular accommodation state in which points 15a, 15b on that depth plane are focused. However, the images displayed to the eyes 210, 220 may provide a convergence cue that causes the eyes 210, 220 to converge onto a point 15 that is not located on the depth plane 240. As a result, in some embodiments, the accommodation distance corresponds to the distance from the exit pupils of the eyes 210, 220 to the depth plane 240, while the vergence distance corresponds to the greater distance from the exit pupils of the eyes 210, 220 to point 15. The accommodation distance is different from the vergence distance. As a result, there is an accommodation-vergence-divergence mismatch. Such a mismatch is considered undesirable and can cause discomfort to the user. The mismatch can be caused by distance (e.g., V d -A d ) and can be characterized in terms of diopters.

[0062] It should be understood that in some embodiments, a reference point other than the exit pupil of the eye 210, 220 may be used to determine distance for determining accommodation-vergence mismatch, so long as the same reference point is used for accommodation distance and vergence distance. For example, distance may be measured from the cornea to the depth plane, from the retina to the depth plane, from the eyepiece (e.g., a waveguide in a display device) to the depth plane, etc.

[0063] Without being limited by theory, it is believed that a user may still perceive an accommodation-vergence-divergence mismatch of up to about 0.25 diopters, up to about 0.33 diopters, and up to about 0.5 diopters as physiologically correct without the mismatch itself causing significant discomfort. In some embodiments, a display system disclosed herein (e.g., display system 250, FIG. 6 ) presents images to a viewer with an accommodation-vergence-divergence mismatch of about 0.5 diopters or less. In some other embodiments, the accommodation-vergence-divergence mismatch of images provided by the display system is about 0.33 diopters or less. In still other embodiments, the accommodation-vergence-divergence mismatch of images provided by the display system is about 0.25 diopters or less, including about 0.1 diopters or less.

[0064] Furthermore, head and eye movements are coordinated with the "vestibular-ocular reflex," which stabilizes image information relative to the retina during head rotation, thus keeping the image information of an object approximately centered on the retina. In response to head rotation, the eyes reflexively and proportionally rotate in the opposite direction to maintain stable fixation on the object. As a result of this compensation relationship, many people can read a book while shaking their head back and forth. (Interestingly, if the book is panned back and forth at the same speed with the head remaining approximately stationary, this would generally not be the case; that is, the person would likely be unable to read a moving book. In other words, the vestibular-ocular reflex is one of the head and eye movement coordinations and is generally not developed for hand movements.) This paradigm can be advantageous for patient-worn health systems because a user's head movement can be relatively directly related to eye movement, and the system is preferably configured to cooperate with this relationship. Therefore, when designing a patient-worn or stationary display-based health system, the characteristics, and sometimes limitations, of the human eye are preferably taken into consideration to provide meaningful virtual reality content that cooperates with the eye's natural mechanisms rather than exerting stress. Furthermore, in the context of health-related applications of augmented reality display systems, this can provide various advantages as disclosed herein. As mentioned above, the health system's display may be implemented independently of an augmented reality (AR) system, although many of the following embodiments are described in conjunction with an AR system for illustrative purposes only.

[0065] FIG. 5 illustrates aspects of an approach for simulating a three-dimensional image by modifying wavefront divergence. The display system includes a waveguide 270 configured to receive light 770 encoded with image information and output the light to a user's eye 210. The waveguide 270 may output light 650 with a defined amount of wavefront divergence corresponding to the wavefront divergence of a light field generated by a point on a desired depth plane 240. In some embodiments, the same amount of wavefront divergence is provided for all objects presented on that depth plane. In addition, the user's other eye will be illustrated as being provided with image information from a similar waveguide.

[0066] In some embodiments, a single waveguide may be configured to output light with a set wavefront divergence corresponding to a single or limited number of depth planes, and / or the waveguide may be configured to output light of a limited range of wavelengths. As a result, in some embodiments, multiple or stacked waveguides may be utilized to provide different wavefront divergences for different depth planes and / or output light of different ranges of wavelengths. As used herein, it should be understood that a depth plane may follow the contour of a flat or curved surface. In some embodiments, for convenience, a depth plane may follow the contour of a flat surface.

[0067] 6 illustrates an example of a waveguide stack for outputting image information to a user. Display system 250 includes a stack of waveguides or stacked waveguide assembly 260 that can be utilized to provide a three-dimensional perception to the eye / brain using multiple waveguides 270, 280, 290, 300, 310. It should be understood that display system 250 may be considered a light field display in some embodiments. Additionally, waveguide assembly 260 may also be referred to as an eyepiece.

[0068] In some embodiments, display system 250 may be configured to provide a substantially continuous cue for convergence and multiple discrete cues for accommodation. The cues for convergence may be provided by displaying different images to each of the user's eyes, and the cues for accommodation may be provided by outputting light that forms images with selectable discrete amounts of wavefront divergence. In other words, display system 250 may be configured to output light with variable levels of wavefront divergence. In some embodiments, each discrete level of wavefront divergence corresponds to a particular depth plane and may be provided by a particular one of waveguides 270, 280, 290, 300, and 310.

[0069] Continuing with reference to FIG. 6 , the waveguide assembly 260 may also include multiple features 320, 330, 340, 350 between the waveguides. In some embodiments, the features 320, 330, 340, 350 may be one or more lenses. The waveguides 270, 280, 290, 300, 310 and / or multiple lenses 320, 330, 340, 350 may be configured to transmit image information to the eye using various levels of wavefront curvature or ray divergence. Each waveguide level may be associated with a particular depth plane and configured to output image information corresponding to that depth plane. The image injection devices 360, 370, 380, 390, 400 may act as light sources for the waveguides and may be utilized to inject image information into the waveguides 270, 280, 290, 300, 310, each configured to disperse incident light across each individual waveguide for output toward the eye 210, as described herein. Light exits output surfaces 410, 420, 430, 440, 450 of the image injection devices 360, 370, 380, 390, 400 and is injected into corresponding input surfaces 460, 470, 480, 490, 500 of the waveguides 270, 280, 290, 300, 310. In some embodiments, each input surface 460, 470, 480, 490, 500 may be an edge of the corresponding waveguide or may be a portion of a major surface of the corresponding waveguide (i.e., one of the waveguide surfaces that directly faces the world 510 or the viewer's eye 210). In some embodiments, a single beam of light (e.g., a collimated beam) may be launched into each waveguide, outputting a total field of cloned collimated beams that are directed toward the eye 210 at a particular angle (and divergence) corresponding to the depth plane associated with the particular waveguide. In some embodiments, a single one of the image launch devices 360, 370, 380, 390, 400 may be associated with and launch light into multiple (e.g., three) waveguides 270, 280, 290, 300, 310.

[0070] In some embodiments, each of the image input devices 360, 370, 380, 390, 400 is a discrete display that generates image information for input into a corresponding waveguide 270, 280, 290, 300, 310. In some other embodiments, the image input devices 360, 370, 380, 390, 400 are the output of a single multiplexed display that may, for example, send image information via one or more optical conduits (such as fiber optic cables) to each of the image input devices 360, 370, 380, 390, 400. It should be understood that the image information provided by the image input devices 360, 370, 380, 390, 400 may include light of different wavelengths or colors (e.g., different primary colors, as discussed herein).

[0071] In some embodiments, light injected into the waveguides 270, 280, 290, 300, 310 is provided by a light projector system 520, which includes a light module 530, which may include a light emitter such as a light emitting diode (LED). Light from the light module 530 may be directed and modified by a light modulator 540, e.g., a spatial light modulator, via a beam splitter 550. The light modulator 540 may be configured to vary the perceived intensity of the light injected into the waveguides 270, 280, 290, 300, 310 and encode the light with image information. Examples of spatial light modulators include liquid crystal displays (LCDs), including liquid crystal on silicon (LCOS) displays. It should be understood that image injection devices 360, 370, 380, 390, 400 are illustrated diagrammatically, and in some embodiments, these image injection devices may represent different light paths and locations within a common projection system configured to output light into associated ones of waveguides 270, 280, 290, 300, 310. In some embodiments, the waveguides of waveguide assembly 260 may function as ideal lenses, relaying light injected into the waveguides to the user's eye. In this concept, the object may be a spatial light modulator 540, and the image may be an image on a depth plane.

[0072] In some embodiments, the display system 250 may be a scanning fiber display comprising one or more scanning fibers configured to project light in various patterns (e.g., raster scan, spiral scan, Lissajous pattern, etc.) into one or more waveguides 270, 280, 290, 300, 310 and ultimately to the viewer's eye 210. In some embodiments, the illustrated image injection devices 360, 370, 380, 390, 400 may diagrammatically represent a single scanning fiber or a bundle of scanning fibers configured to inject light into one or more waveguides 270, 280, 290, 300, 310. In some other embodiments, the illustrated image injection devices 360, 370, 380, 390, 400 may diagrammatically represent multiple scanning fibers or multiple bundles of scanning fibers, each configured to inject light into an associated one of the waveguides 270, 280, 290, 300, 310. It should be understood that one or more optical fibers may be configured to transmit light from the optical module 530 to one or more waveguides 270, 280, 290, 300, 310. It should be understood that one or more intervening optical structures may be provided between the scanning fiber or fibers and one or more waveguides 270, 280, 290, 300, 310, for example, to redirect light exiting the scanning fiber into one or more waveguides 270, 280, 290, 300, 310.

[0073] Controller 560 controls the operation of one or more of stacked waveguide assemblies 260, including the operation of image input devices 360, 370, 380, 390, 400, light source 530, and light module 540. In some embodiments, controller 560 is part of local data processing module 140. Controller 560 contains programming (e.g., instructions in a non-transitory medium) that coordinates the timing and provisioning of image information to waveguides 270, 280, 290, 300, 310, for example, according to any of the various schemes disclosed herein. In some embodiments, the controller may be a single integrated device or a distributed system connected by wired or wireless communication channels. Controller 560 may, in some embodiments, be part of processing module 140 or 150 (FIG. 2).

[0074] Continuing with reference to FIG. 6 , the waveguides 270, 280, 290, 300, and 310 may be configured to propagate light within each individual waveguide by total internal reflection (TIR). Each of the waveguides 270, 280, 290, 300, and 310 may be planar or have another shape (e.g., curved) with major top and bottom surfaces and edges extending between the major top and bottom surfaces. In the illustrated configuration, the waveguides 270, 280, 290, 300, and 310 may each include outcoupling optical elements 570, 580, 590, 600, and 610 configured to extract light from the waveguide by redirecting light propagating within each individual waveguide out of the waveguide and outputting image information to the eye 210. The extracted light may also be referred to as outcoupling light, and the outcoupling optical element light may also be referred to as a light extraction optical element. The extracted beam of light may be output by the waveguide at a location where light propagating within the waveguide strikes the light extraction optical element. The outcoupling optical element 570, 580, 590, 600, 610 may be a grating, for example, including diffractive optical features as discussed further herein. While shown disposed on the bottom major surface of the waveguides 270, 280, 290, 300, 310 for ease of explanation and clarity of the drawings, in some embodiments, the outcoupling optical element 570, 580, 590, 600, 610 may be disposed on the top and / or bottom major surfaces and / or directly within the volume of the waveguides 270, 280, 290, 300, 310, as discussed further herein. In some embodiments, the outcoupling optical elements 570, 580, 590, 600, 610 may be formed within a layer of material that is attached to a transparent substrate and forms the waveguides 270, 280, 290, 300, 310. In some other embodiments, the waveguides 270, 280, 290, 300, 310 may be monolithic pieces of material, and the outcoupling optical elements 570, 580, 590, 600, 610 may be formed on a surface of and / or within that piece of material.

[0075] Continuing with reference to FIG. 6 , as discussed herein, each waveguide 270, 280, 290, 300, 310 is configured to output light and form an image corresponding to a particular depth plane. For example, the waveguide 270 closest to the eye may be configured to deliver collimated light (injected into such waveguide 270) to the eye 210. The collimated light may represent an optical infinity focal plane. The next upper waveguide 280 may be configured to send collimated light that passes through a first lens 350 (e.g., a negative lens) before reaching the eye 210. Such first lens 350 may be configured to generate a slight convex wavefront curvature so that the eye / brain interprets light emerging from the next upper waveguide 280 as emerging from a first focal plane closer inward from optical infinity toward the eye 210. Similarly, the third upper waveguide 290 passes its output light through both the first 350 and second 340 lenses before reaching the eye 210. The combined refractive power of the first 350 and second 340 lenses may be configured to produce another, increasing amount of wavefront curvature so that the eye / brain interprets the light emerging from the third waveguide 290 as originating from a second focal plane closer inward toward the person from optical infinity, where the light from the next upper waveguide 280 was.

[0076] The other waveguide layers 300, 310 and lenses 330, 320 are similarly configured, with the highest waveguide 310 in the stack sending its output through all of the lenses between it and the eye for a collective focal power representing the focal plane closest to the person. To compensate for the stack of lenses 320, 330, 340, 350 when viewing / interpreting light originating from the world 510 on the other side of the stacked waveguide assembly 260, a compensating lens layer 620 may be placed on top of the stack to compensate for the collective power of the lower lens stacks 320, 330, 340, 350. Such a configuration provides as many perceived focal planes as there are available waveguide / lens pairs. Both the waveguide outcoupling optical elements and the focusing sides of the lenses may be static (i.e., not dynamic or electro-active). In some alternative embodiments, one or both may be dynamic using electro-active features.

[0077] In some embodiments, two or more of the waveguides 270, 280, 290, 300, 310 may have the same associated depth plane. For example, multiple waveguides 270, 280, 290, 300, 310 may be configured to output images set at the same depth plane, or multiple subsets of the waveguides 270, 280, 290, 300, 310 may be configured to output images set at the same multiple depth planes, with one set per depth plane. This may provide the advantage of forming tiled images to provide an extended field of view at those depth planes.

[0078] Continuing with reference to FIG. 6 , the outcoupling optical elements 570, 580, 590, 600, 610 may be configured to redirect light from its respective waveguide and output the light with an appropriate amount of divergence or collimation for a particular depth plane associated with that waveguide. As a result, waveguides with different associated depth planes may have different configurations of outcoupling optical elements 570, 580, 590, 600, 610, which output light with different amounts of divergence depending on the associated depth plane. In some embodiments, the light-extraction optical elements 570, 580, 590, 600, 610 may be volume or surface features, which may be configured to output light at specific angles. For example, the light-extraction optical elements 570, 580, 590, 600, 610 may be volume holograms, surface holograms, and / or diffraction gratings. In some embodiments, features 320, 330, 340, 350 may not be lenses. Rather, they may simply be spacers (e.g., cladding layers and / or structures for forming air gaps).

[0079] In some embodiments, the outcoupling optical elements 570, 580, 590, 600, 610 are diffractive features that form a diffraction pattern or "diffractive optical element" (also referred to herein as "DOE"). Preferably, the DOE has a sufficiently low diffraction efficiency so that only a portion of the light in the beam is deflected toward the eye 210 with each intersection point of the DOE, while the remainder continues traveling through the waveguide via TIR. The light carrying the image information is thus split into several related output beams that exit the waveguide at various locations, resulting in a fairly uniform pattern of output emission toward the eye 210 for this particular collimated beam bouncing within the waveguide.

[0080] In some embodiments, one or more DOEs may be switchable between an "on" state in which they actively diffract and an "off" state in which they do not significantly diffract. For example, a switchable DOE may comprise a layer of polymer-dispersed liquid crystal in which microdroplets comprise a diffractive pattern in a host medium, and the refractive index of the microdroplets may be switched to substantially match the refractive index of the host material (in which case the pattern does not significantly diffract incident light), or the microdroplets may be switched to a refractive index that does not match that of the host medium (in which case the pattern actively diffracts incident light).

[0081] In some embodiments, a camera assembly 630 (e.g., a digital camera, including visible and infrared light cameras) may be provided to capture images of the eye 210 and / or tissues surrounding the eye 210 (e.g., to perform eyelid monitoring, pupil monitoring, eye movement monitoring, movement pattern monitoring, blink pattern monitoring, eye color monitoring, etc.), for example, to detect user input and / or monitor a physiological state of the user. As used herein, a camera may be any image capture device. In some embodiments, the camera assembly 630 may include an image capture device and a light source that projects light (e.g., infrared light) onto the eye, which may then be reflected by the eye and detected by the image capture device. In some embodiments, the camera assembly 630 is mounted to a frame 80 (FIG. 9D). The camera assemblies 630 may be electrically connected to processing modules 140 and / or 150, which may process image information from the camera assemblies 630. In some embodiments, one camera assembly 630 may be utilized per eye to monitor each eye separately.

[0082] 7, an example of an output beam output by a waveguide is shown. While one waveguide is illustrated, it should be understood that other waveguides in waveguide assembly 260 (FIG. 6) may function similarly, and that waveguide assembly 260 includes multiple waveguides. Light 640 is launched into waveguide 270 at input surface 460 of waveguide 270 and propagates within waveguide 270 by TIR. At the point where light 640 impinges on DOE 570, a portion of the light exits the waveguide as output beam 650. Output beam 650 is illustrated as being approximately parallel, but may be redirected to propagate to eye 210 at an angle (e.g., divergent output beam formation), as discussed herein, and depending on the depth plane associated with waveguide 270. It should be understood that a nearly collimated exit beam may refer to a waveguide with outcoupling optics that outcouples light to form an image that appears to be set at a depth plane at a large distance (e.g., optical infinity) from the eye 210. Other waveguides or other sets of outcoupling optics may output a more divergent exit beam pattern, which would require the eye 210 to accommodate to a closer distance and focus on the retina, and would be interpreted by the brain as light from a distance closer to the eye 210 than optical infinity.

[0083] In some embodiments, a full-color image may be formed at each depth plane by overlaying an image in each of the primary colors, for example, three or more primary colors. FIG. 8 illustrates an example of a stacked waveguide assembly, with each depth plane including an image formed using multiple different primary colors. The illustrated embodiment shows depth planes 240a-240f, but more or fewer depths are also contemplated. Each depth plane may have three or more primary color images associated with it, including a first image in a first color G, a second image in a second color R, and a third image in a third color B. Different depth planes are indicated in the diagram by different numbers for diopters (dpt) following the letters G, R, and B. By way of example only, the number following each of these letters indicates diopters (1 / m), i.e., the inverse distance of the depth plane from the viewer, and each box in the diagram represents an individual primary color image. In some embodiments, the exact locations of the depth planes for different primary colors may be varied to account for differences in the eye's focusing of light of different wavelengths. For example, different primary color images for a given depth plane may be placed on depth planes corresponding to different distances from the user. Such an arrangement may increase visual acuity and user comfort and / or reduce chromatic aberrations.

[0084] In some embodiments, light for each primary color may be output by a single dedicated waveguide, such that each depth plane may have multiple waveguides associated with it. In such embodiments, each box in the diagram containing the letter G, R, or B may be understood to represent an individual waveguide, and three waveguides may be provided per depth plane, resulting in three primary color images per depth plane. While the waveguides associated with each depth plane are shown adjacent to each other in this drawing for ease of illustration, it should be understood that in a physical device, the waveguides may all be arranged in a stack with one waveguide per level. In some other embodiments, multiple primary colors may be output by the same waveguide, such that, for example, only a single waveguide may be provided per depth plane.

[0085] 8, in some embodiments, G is green, R is red, and B is blue. In some other embodiments, other colors associated with other wavelengths of light, including magenta and cyan, may be used in addition to or replace one or more of red, green, or blue.

[0086] It is understood that references to a given color of light throughout this disclosure will be understood to encompass light of one or more wavelengths within the range of wavelengths of light that are perceived by a viewer to be of that given color. For example, red light may include one or more wavelengths of light within the range of about 620-780 nm, green light may include one or more wavelengths of light within the range of about 492-577 nm, and blue light may include one or more wavelengths of light within the range of about 435-493 nm.

[0087] In some embodiments, the light source 530 (FIG. 6) may be configured to emit light at one or more wavelengths outside the range of a viewer's visual perception, e.g., infrared and / or ultraviolet wavelengths. Additionally, the waveguide incoupling, outcoupling, and other light redirecting structures of the display 250 may be configured to direct and emit this light from the display toward the user's eye 210, e.g., for imaging and / or user stimulation applications.

[0088] Referring now to FIG. 9A , in some embodiments, light impinging on a waveguide may need to be redirected to incoupling the light into the waveguide. An incoupling optical element may be used to redirect and incoupling the light into its corresponding waveguide. FIG. 9A illustrates a cross-sectional side view of an example of a plurality or set 660 of stacked waveguides, each including an incoupling optical element. The waveguides may each be configured to output light of one or more different wavelengths or one or more different wavelength ranges. While stack 660 may correspond to stack 260 ( FIG. 6 ), and the illustrated waveguides of stack 660 may correspond to a portion of multiple waveguides 270, 280, 290, 300, 310, it should be understood that light from one or more of image injection devices 360, 370, 380, 390, 400 is injected into the waveguide from a location requiring the light to be redirected for incoupling.

[0089] The illustrated set 660 of stacked waveguides includes waveguides 670, 680, and 690. Each waveguide includes an associated internal coupling optical element (which may also be referred to as the light input area on the waveguide), for example, internal coupling optical element 700 is disposed on a major surface (e.g., the top major surface) of waveguide 670, internal coupling optical element 710 is disposed on a major surface (e.g., the top major surface) of waveguide 680, and internal coupling optical element 720 is disposed on a major surface (e.g., the top major surface) of waveguide 690. In some embodiments, one or more of the internal coupling optical elements 700, 710, 720 may be disposed on the bottom major surface of the respective waveguides 670, 680, 690 (particularly, one or more of the internal coupling optical elements is a reflective polarizing optical element). As shown, the internal coupling optical elements 700, 710, 720 may be disposed on the upper major surface of the respective waveguide 670, 680, 690 (or on top of the next lower waveguide), and in particular, the internal coupling optical elements are transmissive turning optical elements. In some embodiments, the internal coupling optical elements 700, 710, 720 may be disposed within the body of the respective waveguide 670, 680, 690. In some embodiments, as discussed herein, the internal coupling optical elements 700, 710, 720 are wavelength selective, such that they selectively redirect one or more wavelengths of light while transmitting other wavelengths of light. While illustrated on one side or corner of the respective waveguide 670, 680, 690, it should be understood that the internal coupling optical elements 700, 710, 720 may be disposed within other areas of the respective waveguide 670, 680, 690 in some embodiments.

[0090] As shown, the in-coupling optical elements 700, 710, 720 may be laterally offset from one another. In some embodiments, each in-coupling optical element may be offset to receive light without that light passing through another in-coupling optical element. For example, each in-coupling optical element 700, 710, 720 may be configured to receive light from different image input devices 360, 370, 380, 390, and 400, as shown in FIG. 6 , and may be separated (e.g., laterally spaced) from the other in-coupling optical elements 700, 710, 720 so as to receive substantially no light from others of the in-coupling optical elements 700, 710, 720.

[0091] Each waveguide also includes an associated optically dispersive element, for example, optically dispersive element 730 is disposed on a major surface (e.g., the top major surface) of waveguide 670, optically dispersive element 740 is disposed on a major surface (e.g., the top major surface) of waveguide 680, and optically dispersive element 750 is disposed on a major surface (e.g., the top major surface) of waveguide 690. In some other embodiments, optically dispersive elements 730, 740, 750 may be disposed on the bottom major surfaces of associated waveguides 670, 680, 690, respectively. In some other embodiments, optically dispersive elements 730, 740, 750 may be disposed on both the top and bottom major surfaces of associated waveguides 670, 680, 690, respectively, or optically dispersive elements 730, 740, 750 may be disposed on different ones of the top and bottom major surfaces in different associated waveguides 670, 680, 690, respectively.

[0092] Waveguides 670, 680, 690 may be spaced apart and separated, for example, by gas, liquid, and / or solid layers of material. For example, as shown, layer 760a may separate waveguides 670 and 680, and layer 760b may separate waveguides 680 and 690. In some embodiments, layers 760a and 760b are formed from a low refractive index material (i.e., a material having a lower refractive index than the material forming the immediately adjacent ones of waveguides 670, 680, 690). Preferably, the refractive index of the material forming layers 760a, 760b is 0.05 or more, or 0.10 or less, than the refractive index of the material forming waveguides 670, 680, 690. Advantageously, the lower refractive index layers 760a, 760b may function as cladding layers that promote total internal reflection (TIR) of light through the waveguides 670, 680, 690 (e.g., TIR between the top and bottom major surfaces of each waveguide). In some embodiments, the layers 760a, 760b are formed from air. Although not shown, it should be understood that the top and bottom of the illustrated set of waveguides 660 may include immediate cladding layers.

[0093] Preferably, for ease of manufacturing and other considerations, the materials forming waveguides 670, 680, 690 are similar or the same, and the materials forming layers 760a, 760b are similar or the same. In some embodiments, the materials forming waveguides 670, 680, 690 may differ between one or more waveguides, and / or the materials forming layers 760a, 760b may differ while still maintaining the various refractive index relationships discussed above.

[0094] 9A, light rays 770, 780, 790 enter the set of waveguides 660. It should be understood that light rays 770, 780, 790 may be injected into the waveguides 670, 680, 690 by one or more image injection devices 360, 370, 380, 390, 400 (FIG. 6).

[0095] In some embodiments, light rays 770, 780, 790 have different properties, e.g., different wavelengths or different wavelength ranges, which may correspond to different colors. Each of the incoupling optical elements 700, 710, 720 deflects incident light such that the light propagates through a respective one of the waveguides 670, 680, 690 by TIR. In some embodiments, each of the incoupling optical elements 700, 710, 720 selectively deflects one or more particular wavelengths of light while transmitting other wavelengths to the underlying waveguide and associated incoupling optical element.

[0096] For example, in-coupling optical element 700 may be configured to selectively deflect light ray 770 having a first wavelength or wavelength range while transmitting light rays 780 and 790 having different second and third wavelengths or wavelength ranges, respectively. Transmitted light ray 780 impinges on and is deflected by in-coupling optical element 710, which is configured to deflect light of the second wavelength or wavelength range. Light ray 790 is deflected by in-coupling optical element 720, which is configured to selectively deflect light of the third wavelength or wavelength range.

[0097] 9A , the deflected light rays 770, 780, 790 are deflected to propagate through the corresponding waveguides 670, 680, 690. That is, the in-coupling optical element 700, 710, 720 of each waveguide deflects the light into its corresponding waveguide 670, 680, 690, in-coupling the light into the corresponding waveguide. The light rays 770, 780, 790 are deflected at an angle that causes the light to propagate through the respective waveguides 670, 680, 690 by TIR. The light rays 770, 780, 790 propagate through the respective waveguides 670, 680, 690 by TIR until they impinge on the waveguide's corresponding optical dispersive element 730, 740, 750.

[0098] 9B, a perspective view of the multiple stacked waveguide embodiment of FIG. 9A is illustrated. As previously described, in-coupled light rays 770, 780, 790 are deflected by in-coupling optical elements 700, 710, 720, respectively, and then propagate by TIR within waveguides 670, 680, 690, respectively. Light rays 770, 780, 790 then impinge on optically dispersive elements 730, 740, 750, respectively. Optically dispersive elements 730, 740, 750 deflect light rays 770, 780, 790 to propagate toward out-coupling optical elements 800, 810, 820, respectively.

[0099] In some embodiments, the optically dispersive elements 730, 740, 750 are orthogonal pupil expanders (OPEs). In some embodiments, the OPEs deflect or disperse light into the out-coupling optical elements 800, 810, 820, and in some embodiments, may also increase the beam or spot size of this light as it propagates into the out-coupling optical elements. In some embodiments, the optically dispersive elements 730, 740, 750 may be omitted, and the in-coupling optical elements 700, 710, 720 may be configured to deflect light directly into the out-coupling optical elements 800, 810, 820. For example, with reference to FIG. 9A , the optically dispersive elements 730, 740, 750 may be replaced with the out-coupling optical elements 800, 810, 820, respectively. In some embodiments, the outcoupling optical elements 800, 810, 820 are exit pupils (EPs) or exit pupil expanders (EPEs) that direct light toward the viewer's eye 210 ( FIG. 7 ). It should be understood that an OPE may be configured to increase the size of the eyebox in at least one axis, and that the EPE may increase the eyebox in an axis that intersects the axis of the OPE, e.g., orthogonal to the axis of the OPE. For example, each OPE may be configured to redirect a portion of the light striking the OPE to an EPE of the same waveguide, while allowing the remaining portion of the light to continue propagating down the waveguide. Upon striking the OPE, again, another portion of the remaining light is redirected to the EPE, and the remainder of that portion continues to propagate further down the waveguide, etc. Similarly, upon striking the EPE, a portion of the impinging light is directed out of the waveguide toward the user, and the remaining portion of that light continues to propagate through the waveguide until it again strikes an EP, at which point another portion of the impinging light is directed out of the waveguide, etc. As a result, a single beam of internally coupled light may be "replicated" each time a portion of that light is redirected by an OPE or EPE, thereby forming a cloned beam field of light, as shown in Figure 6. In some embodiments, the OPE and / or EPE may be configured to modify the size of the beam of light.

[0100] 9A and 9B, in some embodiments, a waveguide set 660 includes, for each primary color, waveguides 670, 680, 690, in-coupling optical elements 700, 710, 720, optically dispersive elements (e.g., OPEs) 730, 740, 750, and out-coupling optical elements (e.g., EPs) 800, 810, 820. The waveguides 670, 680, 690 may be stacked with an air gap / cladding layer between each one. The in-coupling optical elements 700, 710, 720 redirect or deflect incident light into their respective waveguides (with different in-coupling optical elements receiving light of different wavelengths). The light then propagates at an angle that will result in TIR within the individual waveguides 670, 680, 690. In the example shown, light ray 770 (e.g., blue light) is polarized by the first in-coupling optical element 700 in the manner described above, then continues bouncing down the waveguide, interacting with the optically dispersive element (e.g., OPE) 730 and then the out-coupling optical element (e.g., EP) 800. Light rays 780 and 790 (e.g., green and red light, respectively) pass through waveguide 670, with light ray 780 incident on and deflected by in-coupling optical element 710. Light ray 780 will then bounce down waveguide 680, via TIR, to its optically dispersive element (e.g., OPE) 740 and then the out-coupling optical element (e.g., EP) 810. Finally, light ray 790 (e.g., red light) passes through waveguide 690 and impinges on the optically in-coupling optical element 720 of waveguide 690. The light in-coupling optical element 720 deflects the light ray 790 so that it propagates by TIR to the light dispersive element (e.g., OPE) 750 and then by TIR to the out-coupling optical element (e.g., EP) 820. The out-coupling optical element 820 then finally out-couples the light ray 790 to a viewer, who also receives the out-coupled light from the other waveguides 670, 680.

[0101] FIG. 9C illustrates a top-down plan view of an example of the multiple stacked waveguides of FIGS. 9A and 9B. As shown, waveguides 670, 680, 690 may be vertically aligned, along with each waveguide's associated optically dispersive elements 730, 740, 750 and associated out-coupling optical elements 800, 810, 820. However, as discussed herein, the in-coupling optical elements 700, 710, 720 are not vertically aligned. Rather, the in-coupling optical elements are preferably non-overlapping (e.g., laterally spaced apart, as seen in the top-down view). As discussed further herein, this non-overlapping spatial arrangement facilitates the injection of light from different sources into different waveguides on a one-to-one basis, thereby allowing a specific light source to be uniquely coupled to a specific waveguide. In some embodiments, arrays including non-overlapping, spatially separated in-coupling optical elements may be referred to as shifted-pupil systems, and the in-coupling optical elements in these arrays may correspond to sub-pupils.

[0102] 9D illustrates an example of a wearable display system 60 into which the various waveguide and associated systems disclosed herein may be integrated. In some embodiments, the display system 60 is the system 250 of FIG. 6, which diagrammatically illustrates some portions of the system 60 in greater detail. For example, the waveguide assembly 260 of FIG. 6 may be part of the display 70.

[0103] 9D , display system 60 includes display 70 and various mechanical and electronic modules and systems to support the functionality of display 70. Display 70 may be coupled to frame 80, which is wearable by a display system user or viewer 90 and configured to position display 70 directly in front of the user's 90's eye. Display 70, in some embodiments, may be considered an eyepiece. In some embodiments, speaker 100 is coupled to frame 80 and configured to be positioned adjacent to the user's 90 ear canal (in some embodiments, another speaker, not shown, may optionally be positioned adjacent the user's other ear canal to provide stereo / shapeable sound control). Display system 60 may also include one or more microphones 110 or other devices to detect sound. In some embodiments, the microphones are configured to allow a user to provide input or commands to system 60 (e.g., voice menu command selections, natural language queries, etc.) and / or enable audio communication with other persons (e.g., other users of similar display systems). The microphone may further be configured as a peripheral sensor to collect audio data (e.g., sounds from the user and / or the environment). In some embodiments, the display system may also include a peripheral sensor 120a, which may be separate from the frame 80 and mounted on the body of the user 90 (e.g., the head, torso, limbs, etc. of the user 90). The peripheral sensor 120a, in some embodiments, may be configured to obtain data characterizing a physiological state of the user 90. For example, the sensor 120a may be an electrode. The display system may further include a stimulus delivery module 112. For example, the stimulus delivery module 112 may include a drug dispenser, an ultrasound source, a vibration source, and / or a heat source. In various embodiments, the peripheral stimulus delivery module may be configured to provide therapy and / or alerts (e.g., by providing tactile feedback).

[0104] 9D , display 70 is operably coupled to local data processing module 140 by a communication link 130, such as wired or wireless connectivity, which may be mounted in a variety of configurations, such as fixedly attached to frame 80, fixedly attached to a helmet or hat worn by the user, embedded within headphones, or otherwise removably attached to user 90 (e.g., in a backpack-style configuration, a belt-type configuration). Similarly, sensor 120a may be operably coupled to local processor and data module 140 by a communication link 120b, such as wired or wireless connectivity. Local processing and data module 140 may comprise a hardware processor and digital memory, such as non-volatile memory (e.g., flash memory or a hard disk drive), both of which may be utilized to aid in processing, caching, and storing data. Optionally, local processing and data module 140 may include one or more central processing units (CPUs), graphics processing units (GPUs), dedicated processing hardware, etc. The data may include a) captured from sensors (such as image capture devices (cameras, etc.), microphones, inertial measurement units, accelerometers, compasses, GPS units, wireless devices, gyroscopes, and / or other sensors disclosed herein (e.g., which may be operatively coupled to frame 80 or otherwise attached to user 90)) and / or b) data obtained and / or processed using remote processing module 150 and / or remote data repository 160 (including data related to virtual content), possibly for passage to display 70 after processing or retrieval. Local processing and data module 140 may be operatively coupled to remote processing module 150 and remote data repository 160 by communication links 170, 180, such as via wired or wireless communication links, such that these remote modules 150, 160 are operatively coupled to each other and available as resources to local processing and data module 140.In some embodiments, local processing and data module 140 may include one or more of an image capture device, a microphone, an inertial measurement unit, an accelerometer, a compass, a GPS unit, a wireless device, and / or a gyroscope. In some other embodiments, one or more of these sensors may be mounted on frame 80 or may be a freestanding structure that communicates with local processing and data module 140 by a wired or wireless communication path.

[0105] 9D , in some embodiments, remote processing module 150 may comprise one or more processors configured to analyze and process data and / or image information, and may include, for example, one or more central processing units (CPUs), graphics processing units (GPUs), special-purpose processing hardware, etc. In some embodiments, remote data repository 160 may comprise digital data storage facilities that may be available through the Internet or other networking configurations in a “cloud” resource configuration. In some embodiments, remote data repository 160 may include one or more remote servers, which provide information, for example, information for generating augmented reality content, to local processing and data module 140 and / or remote processing module 150. In some embodiments, all data is stored and all computations are performed within the local processing and data module, allowing for fully autonomous use from the remote module. Optionally, an external system (e.g., one or more processors, one or more computer systems), including a CPU, GPU, etc., may perform at least a portion of the processing (e.g., generating image information, processing data) and provide information to and receive information from modules 140, 150, 160, e.g., via a wireless or wired connection.

[0106] Reference is now made to FIG. 10 , which shows a schematic diagram of an example of various components of an augmented reality display system, including user sensors 24, 28, 30, 32 and environmental sensor 34. In some embodiments, the augmented reality display system may be a mixed reality display system. As shown, user sensors 24, 28, 30, 32 may be configured to detect data regarding a user's state, and environmental sensor 34 may be configured to collect data regarding parameters external to the user. In some embodiments, the display system may be configured to store data associated with and / or characterizing AR content delivered to the user (e.g., time, location, color configuration, volume, etc. of the AR content).

[0107] User sensors will be discussed first. As shown, the augmented reality display system 2010 may include various user sensors, which may also be referred to as inwardly directed sensors. The augmented reality display system 2010 may correspond to system 80 of FIG. 2 and may include a viewer imaging system 22. The system 22 may include a camera 24 (e.g., an infrared, UV, and / or visible light camera) paired with a light source 26 (e.g., an infrared light source) configured to be directed at and monitor the user (e.g., the user's eyes 2001, 2002 and / or surrounding tissue). In some other embodiments, the light source 26 may be configured to emit light and provide a light stimulus to the user. For example, the light source may be configured to generate content that varies in one or more of the following qualities: color, pattern, brightness, two- or three-dimensional expansion or de-expansion in one or more intensities, sharp or blurred focus, higher or lower resolution, enhanced or de-enhanced contrast, motion, lack of motion, higher or lower refresh rate, magnification, shape, intensity, distortion, or other qualities, all of which may change over time. The camera 24 and light source 26 may be operably coupled to the local processing module 70. Such a camera 24 may be configured to monitor one or more of the pupil (including pupil size) or iris of an individual eye, and / or the orientation, shape, and symmetry of tissues surrounding the eye, such as the eyelids or eyebrows, and perform various analyses as disclosed herein. In some embodiments, imaging of the iris and / or retina of the eye may be used for secure identification of the user.

[0108] Continuing with reference to FIG. 10 , camera 24 may be further configured to image the retina and / or iris of an individual eye, such as for diagnostic purposes and / or orientation tracking based on the location of retinal and / or iris features, such as fovea or fundus features. Iris and retinal imaging or scanning may be performed for secure identification of a user, for example, to properly associate user data with a particular user and / or to present private information to appropriate users. In some embodiments, in addition to or as an alternative to camera 24, one or more cameras 28 may be configured to detect and / or monitor various other aspects of a user's situation. For example, one or more cameras 28 may face inward and be configured to monitor the shape, position, movement, color, and / or other properties of a user's non-ocular features, such as one or more facial features (e.g., facial expressions, voluntary movements, involuntary tics). In another embodiment, one or more cameras 28 may face downward and be configured to monitor the position, movement, and / or other features or characteristics of the user's arms, hands, legs, feet, neck, and / or torso.

[0109] In some embodiments, as disclosed herein, the display system 2010 may include a spatial light modulator that variably projects a light beam across a user's retina through a fiber scanner (e.g., image input devices 200, 202, 204, 206, 208 in FIG. 6 ) to form an image. In some embodiments, the fiber scanner may be used in conjunction with or in place of the camera 24 or 28 to, for example, track or image the user's eye. For example, as an alternative to or in addition to a scanning fiber configured to output light, the health system may have a separate light receiving device to receive light reflected from the user's eye and collect data associated with the reflected light.

[0110] 10 , the cameras 24, 28 and light source 26 may be mounted on a frame 64, which may also hold the waveguide stacks 2005, 2006. In some embodiments, the sensors and / or other electronic devices of the display system 2010 (e.g., the cameras 24, 28 and light source 26) may be configured to communicate with a local processing and data module 70 through communication links 76, 70.

[0111] In some embodiments, in addition to providing data about the user, one or both of cameras 24 and 28 may be utilized to track eyes and provide user input. For example, viewer imaging system 22 may be utilized to select items on a virtual menu and / or provide other input to display system 2010, such as to provide user responses in the various tests and analyses disclosed herein.

[0112] In some embodiments, the display system 2010 may include other sensors 30 configured to monitor physiological and / or behavioral aspects of the user. For example, such sensors 30 may include one or more of the sensors described below. Examples of such sensors 30 include sensors configured for ophthalmic testing, such as confocal microscopy sensors, electronystagmography (ENG) sensors, electrooculography (EOG), electroretinography (ERG) sensors, laser Doppler flowmeter (LDF) sensors, photoacoustic imaging and pressure reading sensors, two-photon excitation microscopy sensors, and / or ultrasound sensors. Other examples of sensors 30 include sensors configured for other electrodiagnostic techniques, such as electrocardiography (ECG) sensors, electroencephalography (EEG) sensors, electromyography (EMG) sensors, electrophysiology testing (EP) sensors, event-related potential (ERP) sensors, near-infrared functional brain imaging (fNIR) sensors, low-resolution electromagnetic tomography of the brain (LORETA) sensors, and / or optical coherence tomography (OCT) sensors. Still other examples of sensors 30 include additional physiological sensors, such as a blood glucose meter, a blood pressure monitor, an electrodermal sensor, a photoplethysmography device, sensing equipment for computer-assisted auscultation, a magnetic field detector, and / or a temperature sensor. In some embodiments, the display system 2010 may include motion sensors 32, such as one or more accelerometers, gyroscopes, gesture sensors, gait sensors, balance sensors, and / or IMU sensors. The sensors 30 may also include a CO2 monitoring sensor, a respiration rate sensor, an end-tidal CO2 sensor, and / or a breathalyzer. The sensors 30 may include one or more inwardly directed (toward the user) microphones configured to detect sounds and various characteristics of those sounds, including the intensity and type of detected sounds, the presence of multiple signals, and / or signal location.

[0113] Sensor 30 is shown diagrammatically as connected to frame 64. It should be understood that this connection may take the form of physical attachment to frame 64 and may be anywhere on frame 64, including the temple ends of frame 64 that extend over the user's ears. For example, sensor 30 may be mounted to the temple ends of frame 64 at the points of contact between frame 64 and the user. In some other embodiments, sensor 30 may extend from frame 64 and contact user 60 (FIG. 9D). In still other embodiments, sensor 30 may not be physically attached to frame 64. Rather, sensor 30 may take the form of a peripheral sensor 30a (FIG. 9D), which may be spaced apart from frame 64.

[0114] In some embodiments, the display system 2010 may further include one or more outwardly directed environmental sensors 34 configured to detect objects, stimuli, people, animals, places, or other aspects of the world around the user. For example, the environmental sensors 34 may include one or more cameras, altimeters, barometers, chemical sensors, humidity sensors, temperature sensors, external microphones, thermal imaging sensors, timing devices (e.g., clocks or calendars), or any combination or subcombination thereof. In some embodiments, multiple (e.g., two) microphones may be spaced apart to facilitate sound source location determination. In various embodiments including an environmental sensing camera, the camera may be positioned, for example, facing outward to capture an image similar to at least a portion of the user's normal field of view. The environmental sensors may further include an emitting device configured to receive signals such as a laser, visible light, light of invisible wavelengths, sound (e.g., audible sound, ultrasound, or other frequencies), etc. Physical contact sensors such as strain gauges, curb feelers, or the like may also be included as environmental sensors.

[0115] In some embodiments, the display system 2010 may further include one or more ultrasound probes 1081 configured to direct acoustic energy to or contact a portion of a user's eye (e.g., upper eyelid, eye socket, sclera, cornea, etc.), a portion of the user's head (e.g., forehead, temple, portion of the skull, etc.), a user's face, or a user's neck. The one or more probes 1081 may be configured to transmit ultrasound waves to various regions of the user's eye, head / face, or neck, and to receive ultrasound waves reflected from various regions of the user's eye, head / face, or neck. For example, the one or more probes 1081 may be connected to an ultrasound transmitter 1077 configured to emit ultrasound energy to the user's eye, the user's head, the user's face, or the user's neck, and an ultrasound receiver 1079 configured to receive ultrasound energy reflected and / or scattered from various structures in the user's eye, head, face, or neck. In some embodiments, one or more probes 1081 may be connected to an ultrasound transceiver 1075 that combines both an ultrasound transmitter and receiver. In some embodiments, the display system may be configured to deliver ultrasound energy to various parts of the user's eyes, head, face, or neck without contacting one or more parts of the user's eyes, head / face, or neck. For example, the display system 2010 may include an electromagnetic acoustic transducer (EMAT) configured to deliver ultrasound energy without contacting various parts of the user's anatomy.

[0116] In some embodiments, the display system 2010 may further be configured to receive other environmental inputs, such as GPS location data, weather data, date and time, or other available environmental data, which may be received from the Internet, satellite communication, or other suitable wired or wireless data communication methods. The processing module 70 may be configured to access additional information characterizing the user's location, such as pollen counts, population statistics, air pollution, environmental toxins, information from smart thermostats, lifestyle statistics, or proximity to other users, buildings, or health care providers. In some embodiments, the information characterizing the location may be accessed using a cloud-based or other remote database. The processing module 70 may be configured to obtain such data and / or further analyze data from any one or combination of environmental sensors.

[0117] The display system 2010 may be configured to collect and store data obtained through any of the sensors and / or inputs described above over time. Data received at the device may be processed and / or stored in a local processing module 70 and / or remotely (e.g., in a remote processing module 72 or a remote data repository 74, as shown in FIG. 9D). In some embodiments, additional data, such as date and time, GPS location, or other global data, may be received directly at the local processing module 70. Data regarding content delivered to the user by the system, such as images, other visual content, or audio content, may likewise be received at the local processing module 70.

[0118] Neural connectivity and neuroplasticity I. Neural processing of information, including visual and multisensory processing In various embodiments, the systems and methods described herein may be used to investigate and / or modify the brain's processing of visual and / or other sensory information (e.g., multisensory information). Multisensory information can include auditory and / or visual information. As discussed herein, the display system may monitor a user's objective and / or subjective reactions or responses to stimuli. The stimuli responses may be used to determine defects or abnormalities, for example, to identify neurological disorders associated with the reactions. Examples of objective responses include eye movements, neural signals, and autonomic responses. Examples of eye movements include, but are not limited to, saccades, pursuits, fixations, convergence and divergence, and / or avoidance. Examples of subjective responses to stimuli include the user's psychological or emotional reactions to the stimuli. Thus, the display system may be configured to use visual stimuli responses to determine the presence of various neurological disorders in a user by measuring neural and psychophysical non-conscious (e.g., preconscious and unconscious) and conscious processing of visual stimuli.

[0119] In some embodiments, the display system may be configured to provide a known stimulus (or multiple stimuli) with known characteristics to a user's eye as visual input. After the user's eye receives the stimulus, a neural impulse may be generated and carried to the brain, which may process the information and form a visual perception. An involuntary or voluntary response may then occur in the user. The display system may detect these involuntary or voluntary responses as well as other detected biometric information. From the known stimuli and the measured responses, the display system may compare the responses with expected or otherwise known responses and provide a conclusion regarding the presence of a disorder, such as a neurological disorder, in the user. In some embodiments, the display system may use the response and stimulus information to determine the presence of a disorder or injury in the brain.

[0120] More generally, a display system may be configured to study the overall processing of visual information by the visual system, including the afferent and efferent visual systems. Different visual processing pathways and phenomena may be evaluated by having the system or environment provide stimuli, filter out noise and artifacts from user actions or the environment, measure the user's response to the stimuli, and compare this response to expected or other known responses. Visual processing pathways and phenomena may also be evaluated passively, without providing specific stimuli, as described in more detail below.

[0121] Because the brain processes visual information, at least in part, in a retinotopic manner and sometimes uses specific anatomical structures for specific functions, a display system may be configured to identify and assess various features of a user's brain by using stimuli that allow for the isolation and localization of such processing or other functionality. The display system may determine whether an abnormality exists if visual perception, as inferred by measured user responses, is not as expected. For example, the display system may determine where the injury is located in the visual pathway (e.g., the optic tract or optic chiasm) based on the location of the blind spot detected by the system (e.g., in the nasal or temporal visual field). This conclusion can be drawn because damage to the optic chiasm typically results in blindness laterally, i.e., in the outer temporal visual fields of both eyes (a condition known as bitemporal hemianopsia), while damage to the optic tract typically results in the loss of half of the visual field of each eye on the side opposite the user from the location of the injury to the optic tract. Another example involves identifying damage to the fusiform face region, the face recognition portion of the brain, when a user is unable to recognize faces or distinguish between similar or common stimuli. Yet another example is a lesion on the primary visual cortex, which can cause blindsight in a user when the user responds to visual stimuli without consciously looking at the stimuli. In some embodiments, the display system may determine whether the user has Type 1 blindsight, where the user can guess the aspect of a visual stimulus with a high percentage of accuracy, or Type 2 blindsight, where the user can detect that a visual input change was present within the area of the blind spot.

[0122] In various embodiments, the display system may be configured to determine whether a user may be experiencing a hallucination by determining whether the user is responding to a non-existent external stimulus. For example, if the user is experiencing a hallucination, they may be interacting with a non-existent external stimulus, e.g., by talking to, seeing, or feeling something that is not present (e.g., not detected by the display system's sensors). Hallucinations may be the result of damage to one or more of the brain's sensory pathways. For example, if a lesion is present in the fusiform gyrus face region and signals from the eyes are also damaged in some way, the brain may attempt to resolve the conflicts in input received through these different pathways by creating a solution that provides meaning. The content of the hallucination may be governed by the affected functional area of the brain. Thus, the display system may be configured to detect whether the user is experiencing a hallucination by detecting that the user is responding to a non-existent external stimulus. The presence of a hallucination may be interpreted by the display system as indicating that a lesion may be present in the brain.

[0123] From the identification of an anomaly, the display system may store the measured and calculated parameters in a database. The display system may generate and send an alert to the user or other system or person to provide notification of the identified anomaly. The display system may also generate correction aids for the user to correct the visual anomaly. The display system may store such correction aid information in a database. The display system may store the measured and / or calculated parameters in a user profile for future use.

[0124] Referring now to FIG. 11 , an example of a method for determining the presence of a neurological disorder 2010 using a display system is illustrated. The display system may be display system 80, 1000, or 2010 of FIGS. 9D, 6, and 10, respectively. In some embodiments, method 1700 may be actively initiated by a user and / or clinician, for example, by selecting a particular method 1700 on a menu or otherwise consciously signaling the display system to initiate method 1700. In some other embodiments, the display system may automatically initiate method 1700. For example, the display system may be worn over an extended period of time, e.g., throughout the day, and may monitor the user's behavior in the background so that the display system may detect behavior that may indicate the presence of a disorder or other disorder. Advantageously, the system may automatically initiate a test and diagnose a possible disorder, regardless of the user's knowledge. Initiating a test without the user's knowledge may be advantageous in eliminating bias caused by conscious awareness that a test is being administered. For example, if the display system detects that the user is unable to follow directions from a mapping program, it may initiate a left-right discrimination impairment test to determine whether the user is unable to understand prompts to turn left or right.

[0125] 11 , in block 1710, the display system may be configured to provide stimuli, which may include visual or auditory content displayed to one or both of the user's eyes or auditory content directed to one or both of the user's ears. Additionally, the stimuli may be stimuli in the surrounding environment, and providing the stimuli may involve providing a signal regarding the identity of the stimuli detected by the display system.

[0126] In block 1720, the display system may sense a user response to the stimulus. In some embodiments, the display system may include a physical user interface (e.g., one or more buttons, such as a touch sensor, on the surface of the display system), a virtual user interface (e.g., one or more icons on a virtual touchscreen), an auditory recognition system (e.g., a voice recorder), or a movement recognition system (e.g., a motion detector) to allow the user to indicate their response to the presented image or images. As another example, the display system may include one or more sensors configured to detect the user's response. For example, the display system may include cameras (e.g., cameras 24, 28 of display system 2010, FIG. 10) and / or electrodes (e.g., peripheral sensor electrodes 30a, FIG. 9D) to measure the user's response. In some embodiments, sensors external to the display system may be configured to measure the user's response and communicate the measured data to the display system. Additionally, the display system may also be configured to monitor environmental variables and, for example, correlate those environmental variables with the user response and / or the ultimate conclusion drawn by the display system.

[0127] In block 1730, the display system may be configured to determine whether the measured user responses are indicative of various neurological disorders (e.g., abnormalities), including visual processing disorders. It should be understood that the various determinations made by the display system may be performed by local processing and data module 70 or remote processing module 72 (FIG. 9D). In some other embodiments, the display system may be configured to communicate the user response data obtained in block 1720 from the display system to a remote medical practitioner and / or diagnostic system. The medical practitioner and / or diagnostic system may make or assist in making a neurological disorder determination. For example, the medical practitioner and / or diagnostic system may refine the preliminary determination made by the display system and / or revise the determination (e.g., by reducing the list of possible neurological disorders).

[0128] It should be understood that the various blocks 1710, 1720, 1730 may be implemented in sequence in some embodiments. In some other embodiments, any one or more of these blocks (e.g., one or both of blocks 1710 and 1720) may be repeated before proceeding to a subsequent block. In still other embodiments, one of blocks 1710, 1720, 1730 may be omitted. For example, block 1710 may be omitted, and certain characteristics of the user may simply be observed in block 1720 before the display system makes a conclusion regarding a neurological disorder.

[0129] Neuropsychological testing, including visual perception testing In some embodiments, a display system (e.g., display systems 80, 1000, and 2010 of FIGS. 6, 9D, and 10, respectively) may be configured to perform method 1700 in conjunction with various neuropsychological tests, such as visual perception tests. In such neuropsychological tests, a user may be presented with a visual stimulus (e.g., one or more images) and then asked to perform a task based on their perception of the visual stimulus. For example, a user may be asked to fixate a display and then identify the stimulus's appearance or indicate whether they perceived the stimulus. In some embodiments, to eliminate the potential for bias that can result from placing virtual stimuli on different depth planes or in different locations, the stimuli may be presented so that they are not noticeably absent from different depth planes or locations. In some other embodiments, the stimuli may be placed in slightly different locations (e.g., different vergence-divergence points), but the difference is so small that it is not consciously noticed by the user. Such slightly different locations may provide an advantage by preventing the brain from fusing the two images. Many variations in visual perception testing are contemplated to isolate different structures or mechanisms involved in how the brain perceives stimuli. An exemplary display system configured to implement a method 1700 for conducting visual perception testing will now be described.

[0130] Binocular rivalry In some embodiments, the display system may be configured to conduct visual perception tests, such as binocular rivalry-based tests. Referring to block 1710 in FIG. 11 , in these tests, the display system may be configured to provide stimuli that may include different images displayed to each eye, which may result in conflicts when processing visual input in the brain. Instead of a fusion of two images, such conflicts may cause visual perception to alternate between images as the images compete for perceptual dominance. When the dominant perceptual representation begins to be suppressed, a composite perceptual representation may be perceived, which may then switch to the other, now the dominant perceptual representation. As an example, a first image may be presented to one eye, and a second image different from the first image may be presented to the other eye. When the first image is the dominant perceptual representation, only the first image may be perceived. When the second image is the dominant perceptual representation, only the second image may be perceived. During the alternating transition between the first and second images, a composite image of the first and second images may be perceived.

[0131] In various embodiments, images for each eye may be presented simultaneously, alternately, selectively to one eye, or a combination thereof. The images may trigger rivalry and affect perceptual alternation over time. In some cases, binocular rivalry-based tests may include one or more different types of rivalry. For example, in some embodiments, the presented images may provide contour rivalry by differing in contour or spatial configuration. In contour rivalry, the same image may be perceived differently, such as an image with lines that form a first design (e.g., a vase) when viewed in a first way and a second design (e.g., two faces) when viewed in a second, different way (e.g., by flipping or rotating the image). When such an image is presented to one eye and the inverse of the image is presented to the other eye, the images may compete for perceptual dominance. As another example, in some embodiments, the presented images may provide color rivalry by differing in color configuration. As yet another example, in some embodiments, the presented images may be differentiated in luminance to provide binocular intensity difference.

[0132] It should be understood that a user's perception of a stimulus (e.g., an image) can be affected by various aspects of visual perception, including, but not limited to, interocular inhibition, interocular grouping, and / or the Troxler effect. The occurrence of these aspects of visual perception can be addressed by presenting a particular stimulus in a particular manner. For example, some embodiments may provide interocular inhibition by presenting an image to only one eye. A typical brain may perceive an image until it is suppressed by a blank field, such as when a display system blocks light from reaching the user's eye or displays a blank image, or until the image is suppressed by an image presented to the other eye. As another example, some embodiments may provide interocular grouping by presenting a portion of an image to one eye and another portion of the image to the other eye. The typical brain may reassemble the portions from each eye and perceive a coherent image. As another example, some embodiments may also provide interocular grouping by alternating two different images between the eyes. A typical brain may sometimes perceive only one of the two images for a duration, even if both images continue to alternate. As yet another example, a display system may be configured to provide stimuli that induce the Troxler effect. When focusing on a particular portion of an image, a typical brain may cause spontaneous fading of another portion of the image (e.g., a portion of the image located away from the focused portion) due to retinal adaptation.

[0133] Referring to block 1720 in FIG. 11 , in various embodiments configured to conduct binocular rivalry-based testing, a display system may sense a user's response to stimuli (e.g., by measuring or inferring perceptual states of dominance and / or inhibition). In some embodiments, the display system may include a physical user interface (e.g., one or more buttons, such as touch sensors, on the surface of the display system), a virtual user interface (e.g., one or more icons on a virtual touchscreen), an auditory recognition system (e.g., a voice recorder), or a movement recognition system (e.g., a motion detector), enabling the display system to sense the user's response while allowing the user to indicate their perception in response to a presented image or images. For example, the user may indicate whether they perceived the first image, the second image, and / or the composite image. As another example, the user may indicate the portions and / or colors of the images perceived, whether they perceived a reassembled coherent image, etc.

[0134] As another example, some embodiments may measure a user's response to applied stimuli using sensors that are part of the display system and / or separate from the display system. In some embodiments, the display system may be configured to determine the user's response (e.g., determine the perceived image) by measuring actions governed by the efferent visual system, such as fixations, saccades, pursuits, etc. (e.g., using inward-facing camera 24 ( FIG. 10 )). In some embodiments, the display system may be configured to determine the user's response by displaying images on two or more different depth planes and / or at two or more different locations. Because suppressed images are not perceived, the eyes may change to provide accommodation and / or convergence movements that correct for the dominant image. Thus, the display system may determine the image perceived by the user by measuring (e.g., imaging) the user's eyes and determining the image that corresponds to the accommodation and / or convergence movements of the user's eyes. In some other embodiments, the user's response may be determined by measuring the amount of time spent viewing each image. The amount of time spent on an image may reveal a more dominant (and viewed for a longer duration) image and / or may be tied to determining stimulus preference based on user experience, knowledge, etc. In some other embodiments, optokinetic nystagmus (OKN), visual evoked potentials (VEP), magnetoencephalography (MEG), and / or blood oxygen level-dependent (BOLD) contrast imaging using functional magnetic resonance imaging (fMRI) may be used to infer dominance and / or inhibition perceptual states (e.g., by determining which eye is believed to be actively viewing the image). Using VEP, MEG, and BOLD, dominance and / or inhibition amplitudes may be determined. Using OKN, velocity may be determined.

[0135] Referring to block 1730 in FIG. 11 , in various embodiments, a display system configured to perform binocular rivalry-based testing may be configured to determine whether measured or inferred perceptual dominance and / or inhibition is indicative of a neurological disorder involving various visual perceptions and / or physiological dominance and / or neural connections. It should be understood that the various determinations coupled by the display system may be performed by local processing and data module 70 or remote processing module 72 ( FIG. 9D ). In some other embodiments, a medical professional and / or diagnostic system in communication with the display system may make or assist in making a neurological disorder determination. For example, the medical professional and / or diagnostic system may refine a preliminary determination made by the display system and / or revise the determination (e.g., by reducing the list of possible neurological disorders).

[0136] As an example, the strength of dominance and / or inhibition may be related to the balance of inhibitory (e.g., GABAergic neuronal bursts) and / or excitatory (e.g., glutamatergic neuronal bursts) cortical dynamics. Compared to a typical brain, a longer time to perform a perceptual switch, e.g., to inhibit one image, may indicate a reduced level of GABAergic action. Some embodiments may be used in the assessment of autism, where fewer perceptual switches and reduced rates of perceptual inhibition are generally demonstrated.

[0137] As another example, the contribution of the non-dominant eye in contour rivalry may be suppressed by visuomotor mechanisms (e.g., the pupillary light reflex). Thus, in some embodiments, measured or inferred perceptual suppression may be used to determine whether a user has a visual processing disorder related to visuomotor mechanisms.

[0138] As yet another example, the process of reconstructing portions of an image during interocular grouping may occur outside the input layer of the brain's visual cortex, suggesting that suppressed portions of an image may be represented in the primary visual cortex, even for short durations. Thus, in various embodiments, the strength of a user's ability or inability to reassemble portions of an image may be used to determine whether the user has an abnormality associated with the brain's primary visual cortex.

[0139] In some embodiments, personality and / or social influences on perception may also be analyzed to determine whether the user has a neurological disorder related to personality and / or social influences. When conflict is present, the brain is generally drawn to stronger or more dominant stimuli. For example, if a stimulus presented to one eye includes an image with high contrast and a stimulus presented to the other eye includes an image with lower contrast, the eye will generally be guided by the higher contrast image because the brain distinguishes objects and features based on differences in light and color. Based on experience, as described herein, different learned associations with objects, features, etc. may also exist. If a negative association with an object exists, the brain may suppress it as an avoidance. If a positive association exists, the brain may make the image more dominant. For example, when presented to both eyes with portions of two different images, the user may reassemble (e.g., using interocular grouping) and perceive only one of the two images. In some embodiments, this may be due to positive social or behavioral experiences / associations with the object in the reassembled image. As another example, gaze aversion, as determined from tracking the viewer's eyes, can be due to personality and / or social influences. In some cases, gaze aversion can indicate shyness, guilt, or autism in the user. Gaze aversion can also be indicative of the user's culture (e.g., direct gaze is considered a confrontational posture).

[0140] Monocular vision / alternating pattern In some embodiments, the display system may be configured to conduct visual perception tests, such as monocular visual field-based tests, in which different images are presented to the same eye. Referring back to block 1710 in FIG. 11 , in these tests, the display system may be configured to provide stimuli that may include a first image and a second, different image displayed superimposed on one eye. After viewing the superimposed images for a period of time, the first image may be perceived more clearly than the second image, and then the second image may be perceived more clearly than the first image. At any given time, only the first or second image may be perceived. Without being limited by theory, monocular visual field may be explained as arising by mechanisms similar to those involved in binocular rivalry (e.g., competition for a dominant or suppressed perceptual state) or by persistence of vision and / or eye movements. In some embodiments, the display system may also similarly present one or more images separately to the other eye.

[0141] 11 , in various embodiments configured to conduct a monocular visual field-based test, the display system may sense a user's response to the stimuli (e.g., by measuring the user's perceptual state of dominance and / or inhibition), similar to that described herein with respect to binocular rivalry-based tests. In some embodiments, the display system includes a physical user interface, a virtual user interface, an auditory recognition system, or a movement recognition system, and may enable the user to indicate their perception in response to the presented images (e.g., whether they perceived a superimposed image, an image superimposed with a clearer first image, an image superimposed with a clearer second image, the first image only, and / or the second image only) while enabling the display system to sense the user's response.

[0142] Some embodiments configured to perform monocular visual field-based tests, such as those described herein with respect to binocular rivalry-based tests, may determine a user's response by measuring components of the efferent visual system (e.g., fixations, saccades, pursuits, etc.) by placing images on two different depth planes or at two different locations on a given depth plane and / or by determining the amount of time spent on each image. Matching the user's eye convergence / accommodation with a particular image and / or the amount of time spent on an image may reveal a more dominant image and / or may be linked to determining stimulus preference based on user experience, knowledge, etc. For example, if a user's favorite color is blue, the user may view a first blue image for a longer length of time than a second superimposed red image. Some embodiments may be used to study neuropsychology and visual perception in color-blind people to determine how well they distinguish between two images and whether their eyes change in accommodation and / or convergence (e.g., if the red image is at a different depth plane or in a different location than a second, superimposed green image). In some embodiments, OKN, VEP, MEG, and / or BOLD may also be used to determine a user's response to the images and infer dominance and / or inhibition.

[0143] 11 , in various embodiments, a display system configured to perform a monocular visual field-based test may be configured to determine whether the measured perceptual dominance and / or inhibition is indicative of various neurological disorders involving physiological dominance and / or neural connections. Similar to the examples described with respect to binocular rivalry-based tests, some embodiments may be configured to determine whether a user has a neurological disorder associated with abnormalities in the user's balance of inhibitory and / or excitatory cortical dynamics, visuomotor mechanisms, the primary visual cortex of the brain, personality, and / or social influences.

[0144] Flash Suppression In some embodiments, the display system may be configured to perform visual perception tests, such as flash-suppression-based tests. By presenting different images at distinct flicker rates, the user's visual perception may cause the visible image to become invisible. Referring to block 1710 in FIG. 11 , in such tests, the display system may be configured to provide stimuli, which may include a first image presented to one eye that may be suppressed by a second image flashed to the other eye. The stimuli may be delivered using different frequencies (e.g., different images may be exposed to the viewer using different exposure times or durations), different images, intensities, etc. As an example, a first image may be displayed to a first eye. A blank field may be presented to a second eye. The second image may then be flashed to the second eye (e.g., over the blank field in a location corresponding to the first image in the first eye). The first image is still displayed to the first eye, but the different stimulus of the second image may result in the perception of only the second image. Thus, the second image presented to the second eye may suppress the first image presented to the first eye. Some embodiments may vary the timing of the transition from the first image to the second image.

[0145] Referring to block 1720 in FIG. 11 , in various embodiments configured to perform a flash suppression-based test, the perceptual state of suppression may be measured or inferred by a display system, similar to that described herein with respect to binocular rivalry-based tests. In some embodiments, the display system may include a physical user interface, a virtual user interface, an auditory recognition system, or a movement recognition system, allowing the user to indicate their perception in response to the presented images (e.g., whether they perceived the first image and / or the second image) while enabling the display system to sense the user's response. As described herein with respect to binocular rivalry-based tests, some embodiments configured to perform a flash suppression-based test may determine the user's response by measuring components of the efferent visual system (e.g., fixations, saccades, pursuits, accommodation, convergence and divergence, etc.) by placing images at two different depth planes, at two different locations, and / or by determining the amount of time spent on each image. Matching the user's eye convergence / accommodation with particular images and / or the amount of time spent on an image may reveal a more dominant image and / or may be coupled with determining stimulus preference based on user experience, knowledge, etc. As another example, some embodiments may use OKN, VEP, MEG, and / or BOLD to infer a perceptual state of inhibition (e.g., by determining which eye is believed to be actively viewing the image).

[0146] Referring to block 1730 in FIG. 11 , in various embodiments configured to perform flash suppression-based testing, measured or inferred perceptual suppression may be used by a display system as input to study mechanisms of conscious and / or non-conscious visual processing. For example, in flash suppression, when a second image appears, the first image disappears, even if it is still present. Without being limited by theory, it is understood that the brain receives both inputs, but because the second image is a new stimulus, the brain subconsciously sees both images and filters out the old image, allowing only the new image to be "seen" through conscious perception. Similar to visual processing by people who are cortically blind or have blindsight, visual information can be used to guide behavior in the absence of visual perception due to the dissociation between perceiving objects (features, recognition, etc.) and acting / responding to them. By using flash suppression-based testing, some embodiments may determine the extent of this selective visual attention filter and its cortical blindness, study primary visual cortex (V1)-independent vision, and / or deliver content entirely to the subconscious. Some embodiments may be used for psychological manipulation (e.g., subliminal messages) and / or persuasion, in that a first image may still have a cognitive effect on the processing (e.g., contextual interpretation) of a second image. For example, some embodiments may be used to desensitize a negative trigger (e.g., a second, consciously viewed image) by adding a positive association (a first, subconsciously viewed image). This may be useful for cognitive behavioral therapy, exposure therapy, diversion therapy, etc.

[0147] In one example, some embodiments may be used to study subconscious behavior. For example, some embodiments may have a user subconsciously act on a viewed image and / or elicit a reactive motor response (e.g., touching a first blue image of a ball). The dorsal cortical pathway mediates grasping and reaching movements for visual processing, which is distinct from the ventral cortical pathway, which generally processes the intrinsic features of an object.

[0148] In another example, some embodiments may be used to study how a user subconsciously reacts to a stimulus (e.g., fight or flight) and then provide therapy. The therapy may include exposure therapy (e.g., treatment for post-traumatic stress disorder (PTSD), anxiety disorders, phobias, etc.) and / or desensitization therapy. For example, for a person suffering from arachnophobia, some embodiments may present a first image (e.g., subconsciously viewed) of an attacking spider and a second image (e.g., consciously viewed) of a butterfly. Some embodiments may determine the extent of a trigger (e.g., the person is panicking, as determined by measuring heart rate, pupil dilation, accelerated breathing patterns, etc.) and then provide exposure therapy (e.g., presenting an image of a spider to help overcome the fear).

[0149] Continuous flash suppression In some embodiments, the display system may be configured to conduct a visual perception test, such as a continuous flash suppression-based test. Similar to the flash suppression-based test described herein, during a continuous flash suppression-based test, a user's visual perception may cause visible images to be invisible to the user when the display system presents different images at distinct flicker rates. Referring to block 1710 in FIG. 11 , in such a test, the display system may be configured to provide stimuli that may include a static image presented to one eye that may be suppressed by a series of dynamic images flashed to the other eye. For example, a static image may be displayed to a first eye. The dynamic image may then be flashed to a second eye. While the static image is still displayed to the first eye, the changing nature of the dynamic image may result in the perception of only the dynamic image. Thus, the dynamic image presented to the second eye may suppress the static image presented to the first eye. In some embodiments, the static image may suppress the dynamic image. Compared to other tests, such as binocular rivalry and / or flash suppression-based tests, continuous flash suppression-based tests may allow for deeper and / or longer suppression (e.g., greater than 5, 6, 7, 8, 9, 10, 11, 12 hours, or any range formed by such values). In some embodiments, the suppression may last for 1 or 2 minutes. In some cases, the suppression may last for 3 minutes or more (e.g., 3.5, 4, 4.5, 5 minutes, or any range formed by such values).

[0150] Referring to block 1720 in FIG. 11 , in various embodiments configured to implement a continuous flash suppression-based test, the perceptual state of suppression may be measured or inferred by a display system, similar to that described herein with respect to binocular rivalry-based tests. In some embodiments, the display system includes a physical user interface, a virtual user interface, an auditory recognition system, or a movement recognition system, and the display system may enable the user to indicate their perception in response to the presented images (e.g., whether they perceived static and / or dynamic images) while enabling the user's reaction to be sensed. As described herein with respect to binocular rivalry-based tests, some embodiments configured to implement a continuous flash suppression-based test may determine the user's reaction by measuring components of the efferent visual system (e.g., fixations, saccades, pursuits, accommodation, convergence and divergence, etc.) by placing images at two different depth planes, two different locations, and / or by determining the amount of time spent on each image. Matching the user's eye convergence / accommodation with particular images and / or the amount of time spent on an image may reveal a more dominant image and / or may be coupled with determining stimulus preference based on user experience, knowledge, etc. As another example, some embodiments may use OKN, VEP, MEG, and / or BOLD to infer a perceptual state of inhibition (e.g., by determining which eye is believed to be actively viewing the image).

[0151] Referring to block 1730 in FIG. 11 , in various embodiments configured to perform a continuous flash inhibition-based test, the measured or inferred perceptual inhibition may be used by a display system as input to study mechanisms of preconscious and / or nonconscious visual processing. For example, visual stimuli presented in parallel with a heartbeat may inhibit visual perception and make it more difficult to distinguish, suggesting that cardiac interoceptive signals may influence visual perception. In some embodiments, the display system may be configured to analyze the influence of interoceptive signals on visual perception and whether the user has a visual processing and / or neurological disorder related to cardiac interoceptive signals.

[0152] Additionally, various embodiments may be used similarly to those described herein with respect to embodiments configured to conduct flash suppression-based tests, and in some cases may have a more pronounced effect. For example, some embodiments may create multiple reassociations with images (e.g., stronger subliminal messaging). Static images may have cognitive effects on the processing of flash images, such as contextual interpretation. Thus, some embodiments may be used for psychological manipulation (e.g., subliminal messaging) and / or persuasion, and / or to elicit a reactive motor response to a first static image. This may be useful for cognitive behavioral therapy, exposure therapy, distraction therapy, and the like. For example, some embodiments configured to provide distraction therapy (e.g., burn debridement) may present words or encouragement and support as static underlay images (e.g., subliminally visible) and entertaining images as dynamic images (e.g., consciously visible). As another example, some embodiments configured to provide cognitive behavioral therapy may subliminally (e.g., subliminally) reassociate thought and emotion patterns and alter undesirable behaviors. Some embodiments may also be used to treat mood disorders, insomnia, depression, eating disorders, and the like.

[0153] Movement-induced blindness (MIB) In some embodiments, the display system may be configured to perform a visual perception test, such as a motion-induced blindness-based test. Due to motion in an image, a user's visual perception may cause portions of the visible image to disappear. Referring to block 1710 in FIG. 11 , in such a test, the display system may be configured to provide a stimulus that may include an image having a stationary portion and a moving portion. For example, an image including a stationary portion set against a moving background may be provided to the user's eyes. When the user focuses on a portion of the image (e.g., a stationary or blinking dot in front of the moving background), the stationary portion of the image (e.g., a stationary dot surrounding the focused portion) may appear to disappear. Thus, the moving background may induce blindness in the user to portions of the image.

[0154] Referring to block 1720 in FIG. 11 , in various embodiments configured to perform a motion-induced blindness-based test, the perceptual state of inhibition may be measured similarly to that described herein with respect to binocular rivalry-based testing. In some embodiments, the display system may include a physical user interface, a virtual user interface, an auditory recognition system, or a movement recognition system, and the display system may enable the user to indicate their perception in response to the presented images (e.g., whether they were able to perceive the stationary portion of the image) while allowing the user's response to be sensed. As described herein with respect to binocular rivalry-based testing, some embodiments configured to perform a motion-induced blindness-based test may determine the user's response by measuring components of the efferent visual system (e.g., fixations, saccades, pursuits, accommodation, convergence and divergence movements, etc.) by placing images at two or more different depth planes or two or more different locations and / or by determining the amount of time spent on each image. Matching the user's eye convergence / accommodation with particular images and / or the amount of time spent on an image may reveal a more dominant image and / or may be coupled with determining stimulus preference based on user experience, knowledge, etc. In some embodiments, OKN, VEP, MEG, and / or BOLD may also be used to infer a perceptual state of inhibition (e.g., by determining which eye is believed to be actively viewing the image).

[0155] Referring to block 1730 in FIG. 11 , the measured perceptual suppression may be used by the display system as input to study mechanisms of conscious and / or non-conscious visual processing. Some embodiments may be used to study the range of retinal adaptation. While interocular motion vision may be limited in some cases, static observation may result in a decrease in retinal photoreceptor response. During saccades, conscious perception is absent, while during pursuit, it may be possible to perfectly track an object. Therefore, various embodiments may take this into account and be used when studying saccades and pursuit. For example, a saccade test may be performed. In some embodiments, a new stimulus may be constantly and dynamically projected onto the user, causing a reflex saccade. If the user is unable to suppress the reflex saccade, various embodiments may determine that the user has symptoms of dementia or Parkinson's disease. As another example, a pursuit test may be performed. In some embodiments, if smooth pursuit vision is impaired, some embodiments may determine that the user has symptoms of traumatic brain injury or dementia. If visual tracking is absent, some embodiments may determine that the user has cortical blindness.

[0156] Exercise-induced interocular suppression In some embodiments, the display system may be configured to conduct visual perception tests, such as a motion-induced interocular suppression-based test. Referring to block 1710 in FIG. 11 , in such tests, the display system may be configured to provide stimuli that may include a stationary image presented to one eye and a moving image presented to the other eye. For example, a stationary image may be displayed to a first eye. A moving image may be displayed to a second eye (e.g., with moving content accompanying the location of the content in the first image relative to the first eye and a similar location in the field of view of the second eye). The stationary image is still displayed to the first eye, but the moving image displayed to the second eye may suppress the stationary image (e.g., making the image presented to the fovea invisible). In some cases, the suppression may occur over a relatively long period of time. For example, if a dynamic image is constantly changing and interesting to the user, the level of engagement and interaction (e.g., the suppression time of a static image) will generally increase, and vice versa. In some embodiments, a user may be able to detect flicker at repetition rates below about 60 Hz, 55 Hz, 50 Hz, 45 Hz, 40 Hz, 35 Hz, or 30 Hz. The suppression time may be affected by various other factors, such as image size and variation.

[0157] Referring to block 1720 in FIG. 11 , the perceptual state of inhibition may be measured or inferred by a display system, similar to that described herein with respect to binocular rivalry-based testing. In some embodiments, the display system may include a physical user interface, a virtual user interface, an auditory recognition system, or a movement recognition system, allowing the user to indicate their perception in response to the presented images (e.g., whether they perceived a stationary image and / or a moving image) while enabling the display system to sense the user's response. As described herein with respect to binocular rivalry-based testing, some embodiments configured to perform motion-induced interocular suppression-based testing may determine the user's response by measuring components of the efferent visual system (e.g., fixations, saccades, pursuits, accommodation, convergence and divergence movements, etc.) by placing images at two different depth planes, two different locations, and / or by determining the amount of time spent on each image. Matching the user's eye convergence / accommodation with particular images and / or the amount of time spent on an image may reveal a more dominant image and / or may be coupled with determining stimulus preference based on user experience, knowledge, etc. As another example, some embodiments may use OKN, VEP, MEG, and / or BOLD to infer a perceptual state of inhibition (e.g., by determining which eye is believed to be actively viewing the image).

[0158] Referring to block 1730 in FIG. 11 , in various embodiments configured to perform a motion-induced interocular suppression-based test, measured or inferred perceptual suppression may be used by a display system as input to study mechanisms of conscious and / or non-conscious visual processing. As one example, some embodiments may be used to study the level of visual input from each eye and the suppression of visual input in a low-vision eye, such as in amblyopia. For example, some embodiments may compare the level of processing and perception of a dynamic image in each eye. As another example, some embodiments may be used as a therapy. For example, by presenting and focusing a dynamic image to the low-vision eye, motion-induced interocular suppression may suppress a static image in the high-vision eye, thereby strengthening the visual input from the low-vision eye. Rear Masking

[0159] In some embodiments, the display system may be configured to perform visual perception tests, such as backward masking-based tests, in which visual perception may cause a temporally later presented image to mask an earlier presented image. Referring to block 1710 in FIG. 11 , in such tests, the display system may be configured to provide stimuli that may include a first image briefly presented to a user's eye, followed by a second image also presented to the user's eye. For example, the first image may be displayed to the eye (e.g., displayed for less than or equal to 50 ms, such as 1 ms to 50 ms, 1 ms to 40 ms, or 1 ms to 30 ms). The second image may then be displayed to the eye (e.g., displayed for a duration greater than the first image, such as greater than 50 ms). The relatively immediate presentation of the second image may disable conscious perception of the first image. Thus, the second image may mask the first image.

[0160] Referring to block 1720 in FIG. 11 , in various embodiments configured to perform a backward masking-based test, the perceptual state of inhibition may be measured similarly to that described herein with respect to a binocular rivalry-based test. In some embodiments, the display system includes a physical user interface, a virtual user interface, an auditory recognition system, or a movement recognition system, and the display system may enable the user to indicate their perception in response to the presented images (e.g., whether they perceived the first image, the second image, and / or both images) while enabling the user's response to be sensed. As described herein with respect to a binocular rivalry-based test, some embodiments configured to perform a backward masking-based test may determine the user's response by measuring components of the efferent visual system (e.g., fixation, saccades, pursuit, accommodation, convergence-divergence movements, etc.). Some embodiments may also determine whether the first or second image was perceived by placing the images at two or more different depth planes or at two or more different locations so that accommodation and / or convergence-divergence movements can be measured. Matching the user's eye convergence / accommodation with a particular image and / or the length of time spent on an image can reveal the perceived image. In some embodiments, based on the time required for the eyes to jump to the flashed image, the display system may determine whether the user's response is a voluntary eye movement or a reflex saccade to the new stimulus. Because conscious perception is substantially absent during a saccade, some embodiments may determine the extent of retinal adaptation by testing the user on their comprehension of that first image. Some embodiments may also be used to train visual processing speed and attention, visuospatial processing, and / or memory and executive function. In some embodiments, OKN, VEP, MEG, and / or BOLD may also be used to determine the image perceived by the viewer (e.g., by determining which eye is believed to be actively viewing the image).

[0161] Referring to block 1730 in FIG. 11 , in various embodiments configured to perform backward masking-based testing, the measured perceptual inhibition may be used by a display system as input to study mechanisms of conscious and / or non-conscious visual processing. Some embodiments may be used for psychological manipulation (e.g., subliminal messages) and / or persuasion, in that a first image may still have a cognitive effect on the processing (e.g., contextual interpretation) of a second image. This may be useful for cognitive behavioral therapy, exposure therapy, attention-shifting therapy, desensitization therapy, etc. Some embodiments may also be used to identify abnormal responses to stimuli and diagnose disorders (e.g., triggers from post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), anxiety disorders, phobias, etc.) by comparing responses to specific images between different users.

[0162] Without being limited by theory, it is believed that visually masked images can influence responses by a user (e.g., due to response priming, subliminal messages, psychodrama, etc.). It should be understood that such influence may be beneficially applied to modulate a user's response to various stimuli and assist the user in achieving a desired response. In some embodiments, masked images may be used to calm a user in high-stress environments. For example, in an environment where a display system determines that a user is viewing an object known to elicit a strong negative emotional response, the display system may be configured to display a previously established masked image to calm the user. The masked image may include graphics, photographic content, words, etc. As described herein with respect to continuous flash-suppression-based testing, some embodiments may reassociate a calming feeling with an object having a strong negative emotional response by, for example, displaying a calming stimulus, which may be visual and / or auditory.

[0163] In some embodiments, the effectiveness of a masked image in influencing user responses may be efficiently determined using a display system. For example, a user may wear a display system every day, so there are multiple opportunities each day to test the effectiveness of different masked images. As a result, in some embodiments, blocks 1720 and 1730 may be performed at different times over a day or several days (e.g., daily) using varying masked images, and the user's responses to the masked images, which may be correlated with other environmental variables or biometric data, may be classified by the display system. As a result, a database of masked images and expected user responses may be built. The display system may then access this database and provide an appropriate masked image depending on the resulting user responses.

[0164] Forward Masking In some embodiments, the display system may be configured to perform a visual perception test, such as a forward-masking-based test, in which a first image presented earlier may mask a second image presented later. Referring to block 1710 in FIG. 11 , in such a test, the display system may be configured to provide stimuli that may include a first image and a second image. For example, the first image may be displayed to the eye (e.g., for a duration longer than the duration for which the subsequent second image is displayed, such as greater than 50 ms). The second image may then be displayed to the eye (e.g., for a duration less than or equal to 50 ms, such as 1 ms to 50 ms or 1 ms to 30 ms). Thus, the first image may mask the second image.

[0165] Referring to block 1720 in FIG. 11 , in various embodiments configured to perform a forward masking-based test, the perceptual state of inhibition may be measured similarly to that described herein with respect to a binocular rivalry-based test. In some embodiments, the display system includes a physical user interface, a virtual user interface, an auditory recognition system, or a movement recognition system, and the display system may enable the user to indicate their perception in response to the presented images (e.g., whether they perceived the first image, the second image, and / or both images) while enabling the user's response to be sensed. As described herein with respect to a binocular rivalry-based test, some embodiments configured to perform a forward masking-based test may determine the user's response by measuring components of the efferent visual system (e.g., fixation, saccades, pursuit, accommodation, convergence-divergence movements, etc.). Some embodiments may also determine whether the first or second image was perceived by placing the images on two different depth planes or at two different locations so that accommodation and / or convergence-divergence movements can be measured. Matching the user's eye convergence / accommodation with a particular image and / or the length of time spent on an image can reveal the perceived image. In some embodiments, based on the time required for the eyes to jump to the flashed image, the display system may determine whether the user's response is a voluntary eye movement or a reflex saccade to the new stimulus. Because conscious perception is substantially absent during a saccade, some embodiments may determine the extent of retinal adaptation by testing the user's comprehension of that first image. Some embodiments may also be used to train visual processing speed and attention, visuospatial processing, and / or memory and executive function. In some embodiments, OKN, VEP, MEG, and / or BOLD may also be used to determine the image perceived by the viewer (e.g., by determining which eye is believed to be actively viewing the image).

[0166] Referring to block 1730 in FIG. 11 , in various embodiments configured to perform forward masking-based testing, the measured perceptual inhibition may be used by a display system as input to study mechanisms of conscious and / or non-conscious visual processing. Some embodiments may be used for psychological manipulation (e.g., subliminal messages) and / or persuasion, in that a first image may still have a cognitive effect on the processing (e.g., contextual interpretation) of a second image. This may be useful for cognitive behavioral therapy, exposure therapy, attention-divertment therapy, desensitization therapy, etc. Some embodiments may also be used to identify abnormal responses to stimuli and diagnose disorders (e.g., triggers from post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), anxiety disorders, phobias, etc.) by comparing responses to different stimuli between different users.

[0167] As disclosed above with backward masking, and without being limited by theory, visually masked images such as those provided by forward masking can influence responses by a user (e.g., due to response priming, subliminal messages, psychodrama, etc.). This ability to influence user responses may be utilized as described above with respect to forward masking.

[0168] Binocular intensity difference (contrast sensitivity) In some embodiments, the display system may be configured to perform a visual perception test, such as a contrast sensitivity-based test, to determine a user's level of contrast sensitivity. Contrast may be determined by the color and luminance of an object relative to a background or other objects in the same field of view. It is noteworthy that a typical eye is generally more sensitive to contrast than absolute luminance. Referring to block 1710 in FIG. 11 , in contrast to a sensitivity-based test, the display system may be configured to provide one or both eyes with images with different levels of contrast (e.g., images with objects having different colors and / or luminances in the same image).

[0169] 11 , in various embodiments configured to perform a contrast sensitivity-based test, the display system may sense a user's response to stimuli (e.g., measure the user's contrast sensitivity) similar to that described herein with respect to binocular rivalry-based testing. In some embodiments, the display system includes a physical user interface, a virtual user interface, an auditory recognition system, or a movement recognition system, and may enable the user to indicate their perception in response to presented images (e.g., whether they were able to perceive an image and / or an image with higher / lower contrast compared to other images) while enabling the display system to sense the user's response. One method of determining a user's response (e.g., determining the image being perceived) includes measuring components of the efferent visual system, such as fixations, saccades, pursuits, etc. Another method for determining a user's response, as disclosed herein, includes placing images with different colors and / or brightness on two different depth planes or at two different locations so that the accommodation and / or convergence / divergence movements of the user's eyes can be measured to determine the image as perceived by the user, thereby allowing the system to determine whether a difference in contrast is perceived.

[0170] Referring to block 1730 in FIG. 11 , in various embodiments, a display system configured to perform a contrast sensitivity-based test may be configured to characterize, monitor, and / or determine a disease associated with visual processing. For example, certain disorders of the retina may cause reduced contrast sensitivity. The disorders may include age-related macular degeneration (ARMD), amblyopia, and lens abnormalities (e.g., cataracts). Thus, some embodiments may be configured to characterize, monitor, and / or determine whether a user has a disease associated with ARMD, amblyopia, or lens abnormalities. As another example, neurological dysfunctions such as Alzheimer's disease and stroke may cause reduced contrast sensitivity. Thus, some embodiments may be configured to characterize, monitor, and / or determine whether a user has a disease associated with Alzheimer's disease and / or stroke. It will be appreciated that characterization and monitoring may be utilized to determine the degree of dysfunction caused by the various diseases and conditions described above, for example, to determine the severity and / or progression of the disease or condition, and thus to recommend or adjust treatment protocols based on biofeedback.

[0171] Mental Status Examination In some embodiments, a display system (e.g., display systems 80, 1000, and 2010 of FIGS. 9D, 6, and 10, respectively) may be configured to obtain and process data from various sensors, identify, track, and / or monitor a user's physical and behavioral responses, and obtain information regarding the user's mental state. Mental state tests may be used to assess and differentiate a patient's cognitive and behavioral functioning. Exemplary display systems configured to perform these diagnostic, therapeutic, and perceptual learning tasks will now be described.

[0172] Short-term mental status test In some embodiments, a wearable display system, such as the systems depicted in FIGS. 6, 9D, and 10, can implement a mental status test or Folstein test to assess a user's cognitive function. The mental status test may be implemented to detect cognitive impairments associated with diseases such as Alzheimer's disease, dementia, or other disorders, and may be administered repeatedly over time to assess a user's cognitive changes and / or response to treatment and / or therapy. For example, with reference to FIG. 9D, administering the mental status test may include detecting responses to images and / or audio presented to the user 60 on the display 62 and / or speaker 66, e.g., microphone 67. With reference to FIG. 10, the system 2010 may monitor the user through an inward-facing camera 24, such as to detect eye position, movement, or gaze. The system 2010 may receive audible responses, such as spoken answers to the mental status test questions, at a sensor 30, which may include a microphone.

[0173] The MMSE test may include multiple simple questions and problems of different types, such as asking the user to provide the current time and location, repeating a list of words, performing simple arithmetic, performing basic motor skills, copying diagrams, and using language for comprehension. The user's responses may be scored individually (e.g., by a clinician observing the test, or by a display system that tracks and matches the user's answers and actions to expected answers and actions), and an aggregate score may be determined. Over time, the same or similar questions and problems may be posed (e.g., automatically posed) to the user, and changes in the user's mental state may be tracked by tracking changes in that score, both for the individual tasks and for the aggregate score. Awakening

[0174] A patient's level of alertness, cognition, or consciousness can be affected by various injuries, diseases, and disorders. Therefore, alertness testing can be implemented to detect injuries, diseases, or disorders that affect mental state. In the context of visual processing and perceptual testing, a patient's level of alertness can also indicate the degree to which the test can be reliably performed. Alertness testing can also be incorporated into any of the various types of cognitive and / or behavioral tests described herein, such as at or near the beginning of the test, to indicate the degree to which the remainder of the test can be reliably performed.

[0175] In some embodiments, the alertness test may be implemented in a wearable display system, such as the systems depicted in FIGS. 9D, 6, and 10. For example, with reference to FIG. 9D, detecting and / or tracking a user's alertness level in an augmented or virtual reality display system 80 may include detecting a response to guiding images and / or audio presented to the user 60 on the display 62 and / or speaker 66. With reference to FIG. 10, the system 2010 may monitor the user through the inward-facing camera 24 for eye tracking, such as detecting eye position, movement, or gaze. For example, the inward-facing camera 24 may detect that the user's eyes are not rotating or accommodating in response to changing images presented by the light source 26, indicating the user has a low alertness level. The inward-facing camera 24 may further be configured to image the user's eyelids and determine eyelid position and / or movement. For example, drooping or closed eyelids may indicate that the user has a low level of arousal (e.g., the user is sleepy), while eyelids that remain wide open may indicate that the user has a high level of arousal. The system 2010 may further monitor the user's head posture, such as via the motion sensor 32, the camera 28, or other sensors 30. For example, the system may detect that the user's head is drooping forward, indicating that the user is asleep. In some embodiments, images from the inward-facing camera 24 may be used to monitor additional indicators, such as heart rate, based on skin color and / or movement magnification, to monitor arousal.

[0176] 11 , the systems and sensors described above may be used according to method 1700 for the detection and / or diagnosis of mental states and / or neurological disorders associated with a user's level of arousal. Any of the steps of method 1700 may be performed, at least in part, by the circuitry of the display depicted in FIGS. 9D , 6 , and 10 , such as processing module 70, remote processing module 72, or other circuitry. Method 1700 may begin at block 1710, where a stimulus is presented to the user. The stimulus may be any type of content delivered to the user through a wearable system, such as the head-mounted system depicted in FIGS. 9D and 10 . For example, the stimulus may be a light pattern, an image, a series of images, a video, a guided image program, or other visual stimulus delivered by display 62 as described above, or a sound or guided audio program delivered by one or more speakers 66. In other embodiments, the stimulus may be an aspect of the user's surrounding environment rather than content presented by display 62 or speaker 66. For example, the stimulus may be a nearby car on the road if the user is driving a car, e.g., if the user is accelerating or drifting between lanes. Thus, presenting the stimulus in block 1710 may be accomplished by the system detecting objects, sounds, movements, or other stimuli in the user's environment and registering and identifying the stimuli. After the stimuli have been presented to the user, method 1700 may continue to block 1720.

[0177] At block 1720, the method may detect a user response to the stimulus indicative of the user's alertness. The user response may include the user's eye movement or position, eye gaze, eyelid, head posture, or other responses, as described herein. The user's alertness level may then be analyzed, determined, estimated, or otherwise quantified based on the detected response. For example, a quality of alertness, such as awareness, drowsiness, fatigue, unconsciousness, or other quality, may be determined based on the user's response to the stimulus. In some embodiments, the user's alertness may be used to determine the user's level or severity of impairment due to a neurological disease. For example, a user with Alzheimer's disease may be more forgetful when fatigued or otherwise not alert than when the user is alert. After the user's response to the stimulus has been observed and the user's alertness level has been analyzed, method 1700 may continue to block 1730.

[0178] At block 1730, method 1700 may determine one or more neurological disorders associated with the detected user response and / or alertness level. The determination at block 1730 may be performed locally and / or remotely and, in some aspects, may include referencing, querying, or otherwise interacting with a database or other repository of diagnostic medical information. For example, a low level of awareness or alertness may indicate disorders such as damage to the brainstem reticular formation, unilateral or bilateral lesions of the thalamus or cerebral hemispheres, and toxic or metabolic disorders. In additional examples, the detected drowsiness may be caused by a variety of disorders, including nervous system disorders such as acute disseminated encephalomyelitis, movement disorders such as Parkinson's disease, memory disorders such as dementia with Lewy bodies, and / or injuries such as traumatic brain injury. In yet another example of a detected neurological disorder, a detected loss of cognition, alertness, or consciousness may be indicative of a nervous system disorder such as epilepsy, neuromyelitis optica, or Schilder's disease, a memory impairment such as Creutzfeldt-Jakob disease or dementia with Lewy bodies, and / or an injury such as a stroke, cerebral aneurysm, or traumatic brain injury. The display system may be configured to conclude that the user is suffering from any of the above disorders based on a match between observed user responses and expected symptoms of the various disorders.

[0179] 12 , the systems and sensors described above may be used for therapy applications according to method 1800. Therapy method 1800 may begin at block 1810, where a user stimulus, such as that described above with reference to FIG. 11 , may be sensed or detected. Method 1800 may continue to block 1820, where it is determined that the stimulus is associated with a neurological disorder of the user, such as the neurological disorder described above with reference to FIG. 11 . After the user's neurological disorder is detected, the method may continue to block 1830.

[0180] At block 1830, the method may display sensory aids for the user. The sensory aids may be displayed for the user by any of the display systems and / or elements described herein with reference to FIGS. 9D, 6, and 10, such as a display, a light source, a waveguide stack, or other display element. If the user is detected to have a neurological disorder that impairs alertness, attention, or awareness, the sensory aids for the user may include engaging content to increase the user's alertness. For example, the engaging content may include bright and / or rapidly changing images, images or videos of subjects known to be of interest to the user, or other visual content likely to capture the user's attention. If visual content is already being shown to the user when decreased alertness is detected, the visual content may be modified to increase the user's alertness, such as by increasing brightness or otherwise altering the visual content.

[0181] Note A user's attention level can be affected by various injuries, diseases, and disorders. In the context of visual processing and perceptual testing, a patient's attention level can also indicate the degree to which the test can be performed reliably. Therefore, attention tests may be implemented to detect injuries, diseases, or disorders that affect mental state. Attention tests may also be incorporated into any of the various types of cognitive and / or behavioral tests described herein, such as at or near the beginning of the test, to indicate the degree to which the remainder of the test can be performed. Attention tests may also be implemented as an assessment of student engagement in educational settings. For example, attention tests may be implemented to determine whether a student is learning optimally using visual, auditory, or kinesthetic methods, and the results may be used to more effectively educate students.

[0182] In some embodiments, attention testing may be implemented in a wearable display system, such as the systems depicted in FIGS. 9D, 6, and 10. Referring to FIG. 9D, detecting and / or tracking a user's attention in an augmented or virtual reality display system 80 may include detecting a response to guiding images and / or audio presented to the user 60 on the display 62 and / or speaker 66. Referring to FIG. 10, the system 2010 may monitor the user through the inward-facing camera 24 for eye tracking, such as detecting eye position, movement, or gaze. For example, the inward-facing camera 24 may detect that the user's eyes are not rotating or accommodating in response to changing images presented by the light source 26, indicating that the user's attention is distracted, not focusing, or otherwise exhibiting reduced attention to the images. The system may further monitor the user through additional sensors 30, such as a microphone, to detect speech responses or other sounds (e.g., yawns, sighs, involuntary sounds, or the like) in response to images or audio presented to and / or detected within the wearer's vicinity.

[0183] 11 , the systems and sensors described above may be used according to method 1700 for the detection and / or diagnosis of mental states and / or neurological disorders associated with a user's attention level. Any of the steps of method 1700 may be performed, at least in part, by the circuitry of the display depicted in FIGS. 9D and 10 , such as processing module 70, remote processing module 72, or other circuitry. Method 1700 may begin at block 1710, where a stimulus is presented to the user. The stimulus may be any type of content delivered to the user through a wearable system, such as the head-mounted system depicted in FIGS. 9D and 10 , or may be an aspect of the user's surrounding environment as detected by the wearable system, such as an object, sound, movement, or other environmental stimulus. For example, the stimulus may be a light pattern, an image, a series of images, a video, a guided image program, or other visual stimulus delivered by a display system as described above, or may be a sound or guided audio program delivered by one or more speakers. After the stimulus is presented to the user, the method 1700 may continue to block 1720.

[0184] At block 1720, the method may detect a user response to the stimulus, indicating the user's attention state. In one example, a user in a classroom may not be looking at the teacher or presentation materials (e.g., a whiteboard) during a lesson. Such a user response may be detected based on the user's eye gaze direction as determined by an inward-facing camera of the display system. The user response may include the movement or position of the user's eyes or eye gaze, as described herein. The user's attention level may then be analyzed, determined, estimated, or otherwise quantified based on the detected response. For example, attention quality, such as focus, attention shifting, or other quality, may be determined based on the user's response to the stimulus. After the user's response to the stimulus has been observed and the user's attention level has been analyzed, method 1700 may continue to block 1730.

[0185] At block 1730, method 1700 may determine one or more neurological disorders associated with the detected user response and / or attention level. The determination at block 1730 may be performed locally or remotely and, in some aspects, may include referencing, querying, or otherwise interacting with a database or other repository of diagnostic medical information. As an example, in response to the response measured at block 1720, the display system may determine that a detected inability to maintain attention or avoid distraction may be indicative of a movement disorder, such as Huntington's disease. In additional examples, the display system may determine that the attention-decreasing characteristics are caused by various disorders, including memory disorders such as dementia, Alzheimer's disease, dementia with Lewy bodies, or vascular dementia, attention-deficit hyperactivity disorder, developmental disorders such as Down syndrome, fetal alcohol syndrome, or schizophrenia, and / or injuries such as hydrocephalus.

[0186] Some exemplary types of attention tests that may be implemented using method 1700 will now be described with reference to FIG. 9D and with continuing reference to FIG. 11 . In one embodiment, a user's attention may be tested by presenting the user with a simple task, such as the stimuli in block 1710. For example, speaker 66 may provide audible instructions to the user to recite a sequence, such as letters spelling a word, a provided sequence of numbers, the alphabet, month names, or another suitable sequence, forward and then backward. The user may then utter a response, which may be detected by microphone 67. If the user is able to completely recite the sequence forward and backward, the user may be determined to have a relatively high level of attention and / or not be distractible. If the user is unable to complete the task, the user may be determined to be distractible or otherwise inattentive.

[0187] In another example, the stimulus at block 1710 may include showing the user an array of similar symbols, such as the letters d and p, or the same symbol in different colors. The user may be asked to mark, indicate, or otherwise select a subset of a particular symbol, for example, all instances of the letter d. At block 1720, method 1700 may detect the user's response and evaluate its accuracy. For example, based on the task provided to the user, processing module 70 may analyze or "score" the response based on the number of symbols correctly marked, the number of symbols not marked that the user should have marked, and / or the number of symbols not marked that the user should have marked. The user's attention level may then be determined based on the analysis of the response.

[0188] In another example, method 1700 may be used to conduct a Test of Variables of Attention (TOVA) or a Test of Everyday Attention (TEA). A TOVA or TEA involves repeating blocks 1710 and 1720, with various different stimuli provided to block 1710 as the cycle progresses to more fully analyze the user's attention. For example, as block 1710 is repeated, the user may be given a stimulus task, such as finding symbols in a map, a counting task such as elevator counting with visual aids and / or attention diversion, and / or a lottery task in which the user is prompted to listen for a predetermined "winning number" in a series of audible digits. In some embodiments, a TEA may be performed by passively monitoring the user's performance of a normal task without providing any additional stimuli. For example, a user who is observed to frequently wander and / or constantly look around may have a concentration deficit. The user may be observed to have a higher level of attention on some tasks and become more distracted when asked to perform other tasks. In block 1730, the method 1700 may compare the user's performance of various tasks to more accurately detect the user's neurological disorder.

[0189] 12 , the systems and sensors described above may be used for therapy applications according to method 1800. Therapy method 1800 may begin at block 1810, where a user stimulus, such as that described above with reference to FIG. 11 , may be sensed or detected. Method 1800 may continue to block 1820, where it is determined that the stimulus is associated with a neurological disorder of the user, such as the neurological disorder described above with reference to FIG. 11 . After the user's neurological disorder is detected, the method may continue to block 1830.

[0190] At block 1830, the method may display sensory aids for the user. The sensory aids may be displayed for the user by any of the display systems and / or elements described herein with reference to FIGS. 9D and 10, such as a display, a light source, a waveguide stack, or other display element. In some embodiments, an audible sensory aid may be provided by a speaker, either alone or in addition to a visual sensory aid. If the user is detected to have a neurological disorder that impairs attention, the sensory aid for the user may include engaging content to increase the user's attention. For example, the engaging content may include an active video game to direct, maintain, control, and / or regulate the user's attention. In some embodiments, the sensory aid may include positive or negative reinforcement. For example, the method may present positive reinforcement when the user remains focused on the task for a defined period of time and provide negative reinforcement if the user is frequently distracted.

[0191] orientation In some embodiments, an orientation test may be performed to determine a user's mental orientation state. For example, the orientation test may enable a diagnostic system to determine that a user is confused or otherwise disoriented. The orientation test may be implemented in a wearable display system, such as the systems depicted in FIGS. 9D, 6, and 10. Referring to FIG. 9D, detecting and / or tracking a user's orientation state in an augmented or virtual reality display system 80 may include detecting a response to guiding images and / or audio presented to the user 60 on the display 62 and / or speaker 66. Referring to FIG. 10, the system 2010 may monitor the user for eye tracking, such as to detect eye position, movement, gaze, pupil size, or other characteristics, through the inward-facing camera 24. The inward-facing camera 24 may further be configured to image the user's eyelids and determine eyelid position and / or movement. The system 2010 may further monitor the user's heart rate, sweating, or other physiological signs via peripheral sensors 30a, such as a heart rate sensor, electrodermal activity sensor, or other sensors. For example, a heart rate sensor may detect an elevated heart rate, and the inward-facing camera 24 may detect pupil dilation (dilation of the pupils), indicating that the user is panicking. In another example, if a user is observed to have difficulty speaking (e.g., slurred words), the system 2010 may be able to determine whether the difficulty is due to the user being fatigued (e.g., indicated by a drooping head detected in an accelerometer) or due to a disorder such as a stroke (e.g., indicated by facial muscles not functioning properly detected by an electrodermal activity sensor).

[0192] 11 , the systems and sensors described above may be used according to method 1700 for the detection and / or diagnosis of mental states and / or neurological disorders associated with a user's orientation state. Any of the steps of method 1700 may be performed, at least in part, by the circuitry of the display depicted in FIGS. 9D and 10 , such as processing module 70, remote processing module 72, or other circuitry. Method 1700 may begin at block 1710, where a stimulus is presented to the user. The stimulus may be any type of content delivered to the user through a wearable system, such as the head-mounted system depicted in FIGS. 9D , 6, and 10 , or may be a stimulus in the user's environment as detected by the wearable system, such as an object, sound, movement, or other environmental stimulus. For example, the stimulus may be a light pattern, an image, a series of images, a video, a guided image program, or other visual stimulus delivered by a display system as described above, or may be a sound or guided audio program delivered by one or more speakers. Some stimuli may include interactive instructions that instruct the user to provide a response detectable by a sensor of the system as described above. For example, in a system that includes a microphone, the stimuli may include audible instructions for the user to state the user's name, the user's location, and the date. After the stimuli are presented to the user, method 1700 may continue to block 1720.

[0193] At block 1720, the method may detect a user response to the stimulus, indicative of the user's orientation state. The user response may include the user's eye movement or position, eye gaze, or other responses as described herein. In some embodiments, the user response may include a spoken response detectable by one or more microphones 67. The user's orientation state may then be analyzed, determined, estimated, or otherwise quantified based on the detected response. For example, if the user is instructed to state the user's name, the user's location, and the date, the system may record the user's response with microphone 67. The recorded response from the user may then be analyzed, such as by processing module 70, to determine whether the user provided a complete and accurate answer. If the answer is incomplete or inaccurate, the user may be determined to be at least partially disoriented. Results of the analysis of the user's response may be combined with physiological data, such as pupil size, eye movement, sweating, heart rate, or other signs, to determine whether the user is experiencing confusion, panic, or other signs or symptoms. After the user's response to the stimuli has been observed and the user's orientation state has been analyzed, the method 1700 may continue to block 1730.

[0194] At block 1730, method 1700 may determine one or more neurological disorders associated with the detected user response and / or orientation state. The determining at block 1730 may be performed locally or remotely and, in some aspects, may involve referencing, querying, or otherwise interacting with a database or other repository of diagnostic medical information. For example, the display system may determine that the state of disorientation and / or confusion may be indicative of various neurological disorders, including nervous system disorders such as acute disseminated encephalomyelitis, epilepsy, or neuromyelitis optica; memory disorders such as Alzheimer's disease, Creutzfeldt-Jakob disease, dementia with Lewy bodies, posterior cortical atrophy, or vascular dementia; and / or injuries such as migraine, stroke, or traumatic brain injury.

[0195] 12 , the systems and sensors described above may be used for therapy applications according to method 1800. Therapy method 1800 may begin at block 1810, where a user stimulus, such as that described above with reference to FIG. 11 , may be sensed or detected. Method 1800 may continue to block 1820, where it is determined that the stimulus is associated with a neurological disorder of the user, such as the neurological disorder described above with reference to FIG. 11 . After the user's neurological disorder is detected, the method may continue to block 1830.

[0196] At block 1830, the method may display sensory aids for the user to address the neurological disorder determined in block 1820. The sensory aids may be displayed for the user by any of the display systems and / or elements described herein with reference to FIGS. 9D, 6, and 10, such as a display, a light source, a waveguide stack, or other display element. In some embodiments, an audible sensory aid may be provided by a speaker, either alone or in addition to the visual sensory aid. If the user is detected to have a disorienting neurological disorder, the sensory aids for the user may include content likely to reduce disorientation, such as time and / or location alerts, reminders, or other indicators of people, places, or time. If the user is panicking or confused, the sensory aids may further include images and / or sounds selected to calm the user.

[0197] Memory and learning A user's memory and / or learning ability may be affected by various neurological injuries, diseases, and disorders. Therefore, memory and learning tests may be implemented to detect injuries, diseases, or disorders that affect mental state. Memory training may also be implemented, for example, through kinesthetic learning. In some aspects, memory training may be implemented for the treatment of disorders such as dysgraphia or dyslexia. In some embodiments, memory and learning tests may be implemented in a wearable display system, such as the systems depicted in FIGS. 9D, 6, and 10. Referring to FIG. 9D, detecting and / or tracking a user's memory and learning ability in an augmented or virtual reality display system 80 may include detecting responses to guiding images and / or audio presented to the user 60 on the display 62 and / or speaker 66. Referring to FIG. 10, the system 2010 may monitor the user through an inward-facing camera 24 for eye tracking, such as to detect eye position, movement, gaze, or pupil size. The inward-facing camera 24 may also be configured to monitor other facial indicators, such as eyelid position, facial muscle twitches, squints, or other facial positions or movements. The system 2010 may also monitor one or more microphones 67 for audible responses from the user, such as speech.

[0198] 11 , the systems and sensors described above may be used according to method 1700 for the detection and / or diagnosis of mental states and / or neurological disorders related to a user's memory and learning ability. Any of the steps of method 1700 may be performed, at least in part, by the circuitry of the display depicted in FIGS. 9D, 6, and 10, such as processing module 70, remote processing module 72, or other circuitry. Method 1700 may begin at block 1710, where a stimulus is presented to the user. The stimulus may be any type of content delivered to the user through a wearable system, such as the head-mounted system depicted in FIGS. 9D, 6, and 10, or may be a stimulus in the user's surrounding environment as detected by such a wearable system. For example, the stimulus may be a light pattern, an image, a series of images, a video, a guided image program, or other visual stimulus delivered by a display system as described above, or may be a sound or guided audio program delivered by one or more speakers. After the stimulus is presented to the user, the method 1700 may continue to block 1720.

[0199] At block 1720, the method may detect a user response to the stimulus, indicative of the user's memory and / or learning ability. The user response may include the user's eye movement or position, eye gaze, eyelids, facial muscles, or other responses as described herein. The user response may also include speech or otherwise audible responses detected at one or more microphones. The user's memory, learning, and / or perception ability may then be analyzed, determined, estimated, or otherwise quantified based on the detected responses, as described in more detail below. Additionally, memory impairment may be detected based on facial muscle twitching or squinting when recalling or attempting to remember forgotten or unknown information, as well as dilated pupils or increased heart rate due to panic resulting from memory impairment. Behavioral memory and / or amnesia may be detected based on abnormal behavior, for example, if the user performs a certain behavior too frequently (e.g., the user brushes their teeth multiple times, calls to make an appointment multiple times, etc.). After the user's responses to the stimuli have been observed and the user's memory, learning, and / or perceptual abilities have been analyzed, the method 1700 may continue to block 1730.

[0200] At block 1730, method 1700 may determine one or more neurological disorders associated with the detected user response and / or the user's memory, learning, and / or perceptual abilities. The determining at block 1730 may be performed locally or remotely and, in some aspects, may involve referencing, querying, or otherwise interacting with a database or other repository of diagnostic medical information. For example, the display system may be configured to determine that signs of impaired memory are indicative of a nervous system disorder such as Barro-concentric sclerosis or Schilder's disease; a cognitive impairment such as mild cognitive impairment; an injury such as a brain tumor, hydrocephalus, stroke, or traumatic brain injury; and / or a memory impairment such as dementia, Alzheimer's disease, Creutzfeldt-Jakob disease, dementia with Lewy bodies, or vascular dementia. In additional examples, signs of short-term memory loss may indicate a memory impairment such as corticobasal degeneration, posterior cortical atrophy, or progressive supranuclear palsy. Signs of working memory impairment may be indicative of a developmental disorder such as schizophrenia. In yet another example, signs of dementia may be indicative of a movement disorder such as Huntington's disease and / or a memory disorder such as Creutzfeldt-Jakob disease. Signs of misrecognition of words and / or pictures may be indicative of a memory disorder such as posterior cortical atrophy.

[0201] In some aspects, detected deficits in immediate memory (e.g., an inability to recall content presented in block 1710 within a few seconds of being presented to the user) may indicate abnormalities in memory and attention and / or alertness. If the user's immediate memory is not found to be impaired, but the user has difficulty recalling after a longer period of time, such as one minute, two minutes, five minutes, or a similar time period, damage to limbic memory structures in the medial temporal lobe and / or medial diencephalon may be suggested. Such damage may result in symptoms such as anterograde amnesia and / or retrograde amnesia. Other memory losses may indicate damage to other areas of the brain.

[0202] Some exemplary types of memory and learning tests that may be implemented using method 1700 will now be described with reference to FIG. 9D and with continued reference to FIG. 11 . In one example, method 1700 may be used to test a user's recent memory by presenting the user with information, such as several named items or stories, and asking the user to recall the information after a delay of several minutes, such as three or five minutes, at block 1710. The information may be presented to the user, for example, via display 62 or speaker 66. In some embodiments, the user may be requested to immediately recall the information, such as by speaking into microphone 67, to ensure that the user has learned the information before beginning the delay period. During the delay, the user may be presented with various distractions, such as unrelated sounds or images. At the end of the delay, the user may be asked to repeat the original information. At block 1720, a user response, such as a repetition of the information or an attempt to repeat the information, may be detected at microphone 67. A user's short-term memory capacity may be assessed based on the accuracy of the user's recitation of presented information.

[0203] In another example, method 1700 may test a user's remote memory by asking the user to recall information about a historical event or a verifiable personal event, at block 1710. Method 1700 may also be used to test explicit word and image recognition by providing photographic or sound stimuli, including images, facial photographs, or other recognizable stimuli, and prompting the user to identify the stimuli, at block 1720. The user may provide the requested information or may attempt to do so, such as by speaking a response into a microphone, as described herein. Similar to the recent memory test described above, a user's remote memory may also be assessed based on the accuracy of the user's responses.

[0204] In some embodiments, various memory tests may be administered according to the Wechsler Memory Scale. For example, the tests may include subtests in spatial addition, digit span, design memory, general cognitive screening, logical memory, verbal paired associations, and / or visual recall. In block 1730, the results of the tests may be analyzed to determine a memory index score, including auditory memory, visual memory, visual working memory, immediate memory, and / or delayed memory.

[0205] In various embodiments, method 1700 may be applied for brain assessment. In one example, a user may be presented with a video game or other interactive activity to detect a decline in the user's perceptual abilities. In block 1710, the user may be presented with a series of images, such as a cloud of dots, that may move and / or vary in clarity. The user may be asked to follow the dots with their eyes. In block 1720, the user's ability to follow the dots may be detected based on eye tracking by a display system. In block 1730, the user's ability to follow the dots may be evaluated to determine whether the user has a neurological disorder, such as early-stage dementia or other disability.

[0206] 12 , the systems and sensors described above may be used for therapy applications according to method 1800. Therapy method 1800 may begin at block 1810, where a user stimulus, such as that described above with reference to FIG. 11 , may be sensed or detected. Method 1800 may continue to block 1820, where it is determined that the stimulus is associated with a neurological disorder of the user, such as the neurological disorder described above with reference to FIG. 11 . After the user's neurological disorder is detected, the method may continue to block 1830.

[0207] At block 1830, the method may display a sensory aid for the user. The sensory aid may be displayed for the user by any of the display systems and / or elements described herein with reference to FIGS. 9D, 6, and 10, such as a display, a light source, a waveguide stack, or other display element. If the user is detected to have a neurological disorder that impairs memory, the sensory aid for the user may include alerts, reminders, games, and / or other interactive content designed to improve the user's memory. As another example, the sensory aid may include an alert or notification regarding a time, place, nearby people, objects, or other items that may be forgotten. A user suffering from behavioral amnesia may be prompted to perform necessary actions, including consistent routines, or to perform actions less frequently. In some embodiments, the sensory aid may improve the user's recognition memory by presenting a game, such as a symbol matching exercise. The sensory aid may be taught through multiple learning types (e.g., visual learning, auditory learning, kinesthetic learning, etc.). In an augmented reality system, the sensory aid may be presented as three-dimensional augmented content. Three-dimensional content may provide enhanced spatial memory, such as by navigation within a 3D map for practicing and learning routes to frequently visited destinations. For example, navigation within a 3D map may be used to show a home-dwelling user the route to the grocery store, or to show an Alzheimer's patient living in a nursing home how to get to their room or the cafeteria, or to post warnings to prevent access to doors or stairs, and the like. External triggers may be incorporated as well (e.g., when the user is instructed to return to their room, an overlay, a signal display device, or other visually overlaid indicator may signal that the user has reached the desired destination).

[0208] In some embodiments, as described above, predictive algorithms and / or artificial intelligence methods may be used to provide sensory aids before they are requested. In one example, a microphone and processor in the display system may detect when a question is being asked frequently or repeatedly by a user and, based on the frequency of the question, ultimately provide an answer to the question before it is asked. For example, a user suffering from memory problems may frequently ask for the time and / or date. Based on observing when and how often the user asks these questions, the method may predict and display the time and date, such as all the time, every few minutes, once an hour, or at a time when the user is more likely to ask.

[0209] language A user's language function can be affected by various neurological injuries, diseases, and disorders. In some embodiments, language function testing may be implemented in a wearable display system, such as the systems depicted in FIGS. 9D, 6, and 10. Referring to FIG. 9D, assessment of a user's language function in an augmented or virtual reality display system 80 may include detecting responses to guiding images and / or audio presented to the user 60 on the display 62 and / or speaker 66. Referring to FIG. 10, the system 2010 may monitor audible responses and / or receive any other speech input from the user at one or more microphones 67.

[0210] 11 , the systems and sensors described above may be used according to method 1700 for the detection and / or diagnosis of mental states and / or neurological disorders associated with a user's language function. Any of the steps of method 1700 may be performed, at least in part, by the circuitry of the display depicted in FIGS. 9D and 10 , such as processing module 70, remote processing module 72, or other circuitry. Method 1700 may begin at block 1710, where a stimulus is presented to the user. The stimulus may be any type of content delivered to the user through a wearable system, such as the head-mounted system depicted in FIGS. 9D , 6, and 10 , or may be a stimulus in the user's surrounding environment as detected by the wearable system, such as an object, sound, movement, or other external (environmental) stimulus. For example, the stimulus may be a light pattern, an image, a series of images, a video, a guided image program, or other visual stimulus delivered by a display system as described above, or may be a sound or guided audio program delivered by one or more speakers. In a language testing situation, the user may be instructed by auditory or visually projected instructions to read a passage, answer questions, speak on a particular topic, or otherwise instructed to speak. After the stimuli are presented to the user, method 1700 may continue to block 1720.

[0211] At block 1720, the method may detect a user response to the stimuli, indicative of the user's memory and / or learning ability. The user response may include speech or otherwise audible response detection and / or recording at one or more microphones, as described herein. The user's language ability or function may then be analyzed or evaluated based on the detected or recorded response, as described in more detail below. For example, deficits in the user's language ability may be detected from symptoms such as aphasia, disorganized speech, dyslexia, coprolalia, and / or highly literal translation. After the user's response to the stimuli has been observed and the user's language function has been analyzed, method 1700 may continue to block 1730.

[0212] At block 1730, method 1700 may determine one or more neurological disorders associated with the detected user response and / or the user's language function. The determining at block 1730 may be performed locally or remotely and, in some aspects, may include referencing, querying, or otherwise interacting with a database or other repository of diagnostic medical information. For example, the display system may determine that the user's response to the applied stimuli is indicative of aphasia, which the display system is configured to determine may be indicative of a nervous system disorder such as Barro-concentric sclerosis or epilepsy, a movement disorder such as Huntington's disease, a cognitive disorder such as mild cognitive impairment or auditory / language processing disorder, an injury such as a brain tumor, migraine, or stroke, and / or a memory disorder such as dementia, Alzheimer's disease, corticobasal degeneration, Creutzfeldt-Jakob disease, frontotemporal dementia, primary progressive aphasia, progressive supranuclear palsy, or vascular dementia. In another example, the display system may be configured to recognize that disorganized speech by a user may indicate a memory disorder, such as dementia with Lewy bodies or frontotemporal dementia. In some embodiments, the display system may be configured to recognize that reading difficulties may indicate a cognitive disorder, such as an auditory, language, or visual processing disorder; a memory disorder, such as frontotemporal dementia or posterior cortical atrophy; and / or a learning disorder, such as dyslexia or visuomotor deficits. Additionally, if coprolalia is observed in a user, the display system may be configured to recognize that coprolalia may indicate a movement disorder, such as Tourette's syndrome, and that highly literal translation may be caused by a non-verbal learning disorder. In some aspects, detected deficits in language function may indicate lesions in various regions of the brain. For example, lesions in the dominant frontal lobe (including Broca's area), left temporal and parietal lobes (including Wernicke's area), subcortical white and gray matter structures (including the thalamus and caudate nucleus), and non-dominant hemisphere may be indicated by various disorders described herein.In one example application, the system may be able to distinguish between damage to Broca's area (e.g., when a user understands speech but is unable to speak) and damage to Wernicke's area (e.g., when a user can speak but is unable to understand the speech of others).

[0213] Some exemplary types of language tests that may be implemented using method 1700 will now be described with reference to FIG. 9D and with continued reference to FIG. 11 . In one embodiment, method 1700 may be used to test a user's spontaneous speech by asking the user to speak about general topics, at block 1710. For example, the user may be asked to talk generally about the user's childhood or any other topic likely to elicit spontaneous speech. Speech prompts may be presented to the user, for example, via display 62 or speaker 66. At block 1720, the user's responsive speech may be detected at microphone 67. Processing module 70 may analyze the recorded speech using speech recognition software or other analytical processes. The user's spontaneous speech function may then be evaluated based on factors such as fluency, phrase length, speech rate, and richness of spontaneous speech. The user's spontaneous speech may be further analyzed based on the detection of modulations, errors, neologisms, and / or grammatical errors.

[0214] In another example, method 1700 may test the user's language comprehension by asking the user a question and / or providing a command to the user at block 1710. For example, the question or command presented at block 1710 may solicit a verbal response from the user. At block 1720, microphone 67 or other sensor may detect the user's answer to the simple question and / or response to the simple command provided at block 1710. In some embodiments, the command may require a non-verbal response, which may be detected by a sensor, such as an inward- or outward-facing camera or ambient sensor 30a. The user's compliance with the command may also be detected at block 1720.

[0215] In another example, method 1700 may evaluate the user's ability to name an object or part of an object. In block 1710, display 62 may show the user a picture of a common object, such as a pencil, a watch, or other item, and prompt the user to name the item. Less common (more "difficult") items, such as a belt buckle or a stethoscope, may also be presented. In some embodiments, the difficulty may be increased by asking the user to name part of an object instead of, or in addition to, the entire object. In block 1720, microphone 67 may detect the user's speech response to the visual stimulus. Processing module 70 may use speech recognition software to determine whether the user correctly named the depicted object.

[0216] In some embodiments, method 1700 may be used to test a user's repetition and / or comprehension abilities. In block 1710, the user may be presented with a single word, several words, a short phrase, a longer phrase, a sentence, or other group of words. In a repetition test, the stimulus may be presented audibly, such as by speaker 66. In a comprehension test, the stimulus may be presented visually, such as by showing written words in display 62. The user may then be audibly or visually prompted to repeat or read the stimulus. In block 1720, the user's response may be detected at microphone 67. Processing module 70 may use speech recognition software to determine whether the user accurately read or repeated the stimulus word, word, phrase, sentence, or multiple sentences and evaluate any discrepancies or errors.

[0217] 12 , the systems and sensors described above may be used for therapy applications according to method 1800. Therapy method 1800 may begin at block 1810, where a user stimulus, such as that described above with reference to FIG. 11 , may be sensed or detected. Method 1800 may continue to block 1820, where it is determined that the stimulus is associated with a neurological disorder of the user, such as the neurological disorder described above with reference to FIG. 11 . After it is determined that the user has the identified neurological disorder, the method may continue to block 1830.

[0218] At block 1830, the method may display sensory aids for the user. The sensory aids may be displayed for the user by any of the display systems and / or elements described herein with reference to FIGS. 9D and 10, such as a display, a light source, a waveguide stack, or other display elements. If the user is detected to have a neurological disorder that impairs the user's language function, the sensory aids for the user may include language and / or speech therapy. For example, the user may be notified of speech errors and prompted to correct the errors. In another example, a user who has difficulty reading words or phrases may be prompted, such as by displaying the words or phrases on display 62. In some embodiments, visual content, such as educational materials and language games, may be presented to enhance the user's learning ability and improve the user's language skills.

[0219] Finger agnosia test In some embodiments, the display system may be configured to administer a manual agnosia test. The manual agnosia test may determine a user's ability to name and identify fingers or toes. In certain embodiments, the manual agnosia test may be administered using interactive prompts generated by the display system. The prompts may be visual, auditory, and / or tactile.

[0220] In some embodiments, the manual agnosia test may be implemented in a wearable display system, such as the systems depicted in FIGS. 9D, 6, and 10. With reference to FIG. 9D, detecting and / or tracking a user's response to prompts in an augmented reality display system 80 may include detecting responses to visual content, guiding images, and / or general auditory commands presented to the user 60 using the display 62 and / or speaker 66. With reference to FIG. 10, the system 2010 may monitor the user through an inward-facing camera 24 for eye tracking, such as detecting eye position, movement, or gaze. As disclosed herein, the camera 24 may be used to register user input to the display system (e.g., by tracking the user's eyes and determining their selection of a virtual menu item). In some embodiments, the display system may be configured to receive input via a real input device (e.g., a physical button) and / or a virtual input device (e.g., a virtual button projected by the display device). Such input may include, for example, eye tracking, head pose, and / or gestures.

[0221] Referring now to FIG. 11 , the systems and sensors described herein may implement method 1700 to detect and / or diagnose a neurological disorder associated with manual agnosia in a user. Any of the steps of method 1700 may be performed, at least in part, by the display systems depicted in FIGS. 9D , 6 , and 10 , with processing occurring using processing module 70, remote processing module 72, or other circuitry. At block 1710 of FIG. 11 , a stimulus may be presented to the user by the display system or may be presented by the surrounding environment and identified by the display system. In some embodiments, the stimulus may include a prompt for the user to complete a task. For example, the user may be prompted to identify their left index finger or hold their right hand out in the air. In some embodiments, the user may be prompted to identify a particular finger, position a finger in a particular orientation, or distinguish between multiple fingers. For example, the user may be asked to align a virtual marker with a particular finger, point to a finger with their other hand, and / or focus their eyes on a particular finger.

[0222] In block 1720, the display system may detect a user response to the stimulus. The display system may be configured to sense the user's eye gaze using inward-facing camera 24 and determine whether the user's gaze is on the correct finger. In some other embodiments, the display system may be configured to monitor the user's fingers using environmental sensors 34 and determine whether the correct finger is properly aligned with the virtual marker. The determination in block 1730 may be performed locally and / or remotely and, in some aspects, may include referencing, querying, or otherwise interacting with a database or other repository of diagnostic medical information.

[0223] At block 1730, method 1700 may determine whether the user suffers from manual agnosia based on the user's response to the stimulus determined at block 1720. For example, an inability to consistently identify fingers may be interpreted as being caused by manual agnosia. It should be appreciated that manual agnosia may be caused by Huntington's disease, and the system may be configured to alert the user and / or a third party to the presence of manual agnosia and possible notification of Huntington's disease.

[0224] Because the test is bidirectional, it is possible that a false positive for manual agnosia may result from an inability to understand the instructions provided by the display system. Consequently, in some embodiments, the display system may determine whether an impairment in command comprehension exists, for example, due to an inability to understand the language in which the instructions are presented or a cognitive inability to understand the instructions. It should be understood that the correct language for the instructions may be determined by first presenting a question to the user to confirm understanding of the instructions before proceeding to block 1710 or 1730. In some other embodiments, the display system may analyze the user's eye gaze and the elapsed time since receiving the instruction from the display system to determine whether these parameters indicate confusion and, therefore, a lack of understanding of the instructions. For example, the eyes of a user who does not understand a particular language may not track words displayed by the display system in the same way as a normal speaker of that language would track words, and in some cases, may not linearly follow them from the beginning of the sentence to the end, because the user does not understand those words. In some embodiments, the display system may be configured to measure the elapsed time between the display of the instruction and the user's identification of a finger. A longer elapsed time than the reference time may indicate an inability to understand the instruction.

[0225] 12 , the systems and sensors described above may be used according to method 1800 for therapy applications. At block 1810, in some embodiments, a stimulus directed at a user, such as that described above with reference to the response in FIG. 11 , may be sensed or detected. For example, the display system may be configured to monitor whether the user is directing their gaze toward a finger or toe using various sensors, including environmental sensor 34 or other sensors. At block 1820, in some embodiments, the display system may determine that the stimulus is associated with manual agnosia.

[0226] The display system can be configured to interact with other systems, objects, totems, units, or items and provide therapy. For example, a user may wear a set of clothing (e.g., gloves) configured to provide sensations and / or stimuli (e.g., electrical, mechanical, thermal, biochemical) to the user. In some embodiments, the sensations and / or stimuli can be initiated in response to user input, as described herein. For example, a user may wear gloves configured to provide electrical stimulation using a transcutaneous peripheral nerve stimulation (TENS), electrical muscle stimulator (EMS), and / or powered muscle stimulator (PMS) unit. Continuing with this example, a user may activate electrical stimulation on the user's finger by gazing at the finger. In some embodiments, the provided stimulation can provide many benefits, such as feedback to the user (e.g., closed-loop, tactile), pain relief, increased blood circulation, prevention of muscle atrophy, muscle conditioning, relaxation of muscle spasms, and / or increased muscle support. For example, a user who does not have perfect motor skills in their fingers can receive electrical stimulation initiated by the display system to help compensate for motor skill impairments (e.g., shaking, trembling, weakness).

[0227] In block 1830, the display system may also be configured to display sensory aids for the user. For example, the display system may display a hint or location, identification, or indication of the correct finger or toe. In some embodiments, the displayed virtual content may advantageously be overlaid directly on the correct finger or toe and may be located in the same depth plane as the finger or toe.

[0228] Agraphia Test In some embodiments, a display system (e.g., the display systems depicted in FIGS. 9D, 6, and 10) may be configured to administer an agraphia test to assess a user's ability to write a word or series of words. The display system may administer the agraphia test using interactive prompts. For example, the display system may be configured to administer the agraphia test by asking the user to write their name in space or write a sentence on a piece of paper, which is imaged by the display system.

[0229] Referring now to FIG. 11 , the systems and sensors described herein may implement method 1700 to detect and / or diagnose a neurological disorder associated with agraphia in a user. In block 1710, a stimulus is presented to the user. The stimulus may also be present in the surrounding environment. For example, the display system may observe the user's interaction with one or more objects in the environment surrounding the user. As another example, the display system may observe the user writing something, which may be detected and identified as a stimulus. The stimulus may include a prompt for the user to complete a task. For example, the user may be prompted to write a word or multiple words (e.g., their name, a sentence, a symbol) on a piece of paper, in space, or on / in some other medium. It should be understood that the prompt may be a visual prompt, such as text provided by the display 62, or an auditory prompt, such as an instruction provided through the speaker 66.

[0230] In block 1720, the display system may detect a user response to the stimulus, indicating the presence or absence of agraphia in the user. For example, the display system may be configured to image or otherwise detect the position and movement of the user's hand, any writing implement, and / or text written on a surface. The text may be written physically, e.g., using ink or pencil lead, or virtually, e.g., by using the display system to track the position of the tip of the writing implement and / or the user's fingers and / or gestures. In some embodiments, the text can be written using a virtual and / or physical keyboard.

[0231] In block 1730, the display system may be configured to determine whether the user suffers from agraphia and the extent of the condition. For example, the display system may determine that the user is unable to complete a required task of writing a word. The display system may also be configured to determine the extent to which the user is unable to complete the task. For example, the user may be able to write part of a word. The display system may be configured to determine the severity of the agraphia based on the portion of the task completed by the user. It will be understood that the severity of the agraphia is directly related to the number of tasks (instructions provided by the display system for writing specific content) that have not been completed. In some embodiments, the display system may compare the user's current results with the user's previous results. Such comparisons may be applied to determine the presence of a neurological disease or to determine the progression of the disease. For example, if a user has previously been determined to have Parkinson's disease, the display system may be configured to compare the size and / or legibility of the user's handwriting over time as agraphia tests are conducted periodically over a period of time, e.g., weeks, months, or years. The display system may interpret handwriting that becomes smaller and / or less legible over time as an indication of disease progression.

[0232] The display system can be configured to distinguish between related types of disorders. In some embodiments, multiple tests can be used in combination to more precisely pinpoint a specific type of disorder (e.g., agraphia). For example, the display system may distinguish between pure agraphia and apraxic agraphia by detecting both the user's ability to produce handwritten text (e.g., on paper, in space) and typed text (e.g., on a physical keyboard, using a virtual keyboard). In some embodiments, the display system can compare the results of handwritten text with those of typed text to more precisely pinpoint the user's neurological disorder.

[0233] As discussed above with respect to agnosia, it is possible that a false positive may be obtained due to the user's inability to understand the prompts or tasks required by the display system. As a result, as discussed above with respect to agnosia, the display system may be configured to confirm that the user understands the prompts provided by the display system. For example, the display system may be configured to determine that the user understands the language of the prompts and / or has the cognitive ability to understand the prompts.

[0234] 12 , the systems and sensors described herein may be used according to method 1800 for therapy applications. At block 1810, in some embodiments, the display system may be configured to monitor whether the user has been prompted to write their name or some other word using various sensors, including microphone 67 ( FIG. 9D ), environmental sensor 34 ( FIG. 10 ), downward-facing camera 28 ( FIG. 10 ), or other sensors. At block 1820, in some embodiments, the display system may determine that the stimulus (a request to physically write content) is associated with the user's neurological disorder, such as agraphia.

[0235] As in the discussion regarding agnosia above, in some embodiments, the display system can be configured to interact with other systems, objects, totems, units, or items to provide therapy for agraphia as described herein (e.g., clothing, processors, TENS / EMS / PMS units). In an embodiment, the display system can be configured to use such systems, objects, totems, units, or items to initiate sensations and / or stimuli (e.g., electrical, mechanical, thermal, biochemical) as described herein. In some embodiments, the provided stimuli can provide many benefits as described herein.

[0236] In block 1830, the display system may be configured to display sensory aids for a user with agraphia. For example, the display system may display writing or visual aids to help the user improve their writing or successfully write words, phrases, or sentences. In some embodiments, the display system may display augmented reality content corresponding to words the user is tasked with writing. Additionally, due to the display system's ability to display content on different depth planes, the display system may display sensory aids that appear on the surface on which the user is writing. As a result, in some embodiments, the user may simply trace the word (displayed as augmented reality content) they wish to write.

[0237] Left-right discrimination test In some embodiments, the display system (e.g., the display systems depicted in FIGS. 9D, 6, and 10) may be configured to conduct a left-right discrimination impairment test to test the user's disorientation in identifying body parts. In an embodiment, the left-right discrimination impairment test may be conducted through interactive prompts.

[0238] Referring now to FIG. 11 , the systems and sensors described herein may implement method 1700 to detect and / or diagnose a neurological disorder associated with a user's left-right discrimination impairment (e.g., an inability to distinguish between right and left). In block 1710, the display system may be configured to provide a left-right discrimination impairment test to the user by providing a stimulus. The stimulus may be a prompt for the user to complete a task. For example, the user may be prompted to touch one body part with the fingers of the opposite body part. As a further example, the user may be prompted to touch their left buttock with their right fingers. In some embodiments, the display device may project a stimulus (an image of an object) toward a particular direction. The user may be prompted, for example, to identify the projected direction. In some embodiments, the stimulus may originate from the environment in addition to, or instead of, the display system. For example, the stimulus may be GPS navigation instructions instructing a user to turn in a particular direction while driving.

[0239] In block 1720, the display system may detect a user response to the stimulus, which may indicate the presence or absence of a left-right discrimination impairment in the user. In some embodiments, the display system may be configured to image or otherwise detect the position and movement of the user's hands and / or other body parts to determine whether the prompted task was completed correctly. For example, the display system may utilize microphone 67 (FIG. 9D), environmental sensor 34 (FIG. 10), inward-facing camera 24 (FIG. 10), and / or downward-facing camera 28 (FIG. 10) to determine the user's response to the prompted task, for example, by tracking the user's eye movement or gaze.

[0240] In block 1730, the display system may be configured to determine whether and to what extent the user suffers from left-right discrimination impairment. For example, the display system may determine whether the user correctly performed a given task, such as touching their left buttock with their right fingers. In some other embodiments, the display system may determine whether the user correctly identified the orientation of a projected augmented reality object.

[0241] 12 , the systems and sensors described herein may be used according to method 1800 for therapy applications. At block 1810, in some embodiments, a stimulus directed to a user may be sensed or detected. For example, the display system may be configured to use environmental sensors 34 or microphone 67 to monitor the user's environment and sense whether the user is receiving a stimulus that requires the user to distinguish between left and right directions. For example, the display system may recognize that the user is being oriented (e.g., by the display system itself, by a third party, or by another device). At block 1820, in some embodiments, the display system may determine that the stimulus is associated with left-right discrimination impairment and that the user has such right disorientation.

[0242] In block 1830, the display system may also be configured to display sensory aids to compensate for the user's left-right discrimination impairment. The sensory aids may be, for example, hints, object locations, indicators, or directional reminders. For example, in response to an auditory command (e.g., from a map program, from a third party, etc.) to turn right or left, the display system may simply display an arrow in the user's field of view pointing in the correct direction.

[0243] Calculation Test In some embodiments, the display system may be configured to administer a computational test. For example, such a test may test a user's ability to perform computations (e.g., arithmetic). The computational test may be administered through interactive prompts provided by the display system.

[0244] 11 , the systems and sensors described herein may implement method 1700 to detect and / or diagnose neurological disorders associated with a user's ability to perform calculations successfully. In block 1710, a display system may be configured to provide a calculation test to the user. For example, the display system may display an image or verbal instructions accompanied by an arithmetic problem (e.g., adding two numbers). The stimulus may be an auditory / visual stimulus from the environment. For example, the stimulus may be an arithmetic problem present in the surrounding environment (e.g., an arithmetic problem presented on a whiteboard in a classroom).

[0245] In block 1720, the display system may detect a user response to the stimuli indicative of the user's ability to solve the presented problem. In some embodiments, sensing the response may involve imaging an answer written by the user on a surface or interpreting an answer given verbally by the user. It should be understood that, as with other tests herein, blocks 1710 and 1720 may be repeated multiple times to build a larger data set for later analysis before proceeding to block 1730.

[0246] At block 1730, method 1700 may determine one or more neurological disorders associated with the detected user response. As an example, the display system may be configured to diagnose a memory disorder based on calculation errors (e.g., a user's inability to memorize the multiplication tables). In some embodiments, the display system may determine that a possible cause of the disorder is posterior cortical atrophy.

[0247] 12 , the systems and sensors described above may be used for therapy applications according to method 1800. At block 1810, in some embodiments, the display system may be configured to monitor prompts given to the user (e.g., by a teacher or parents, or when calculating the bill at a restaurant) using various sensors, such as environmental sensors 34 or microphone 67.

[0248] In block 1830, the display system may be configured to display sensory aids for the user to compensate for the inability to perform the calculation. For example, the display system may display missing steps in an arithmetic solution, prompt the user with reminders or hints of the incorrect or missing steps, or identify the correct answer or response to the problem.

[0249] Apraxia test In some embodiments, the display system may be configured to test for apraxia, i.e., the user's inability to follow motor commands. It should be understood that apraxia is different from a motor deficit or inability to understand language. Rather, apraxia results from a failure in the higher-level planning or conceptualization of the motor task being prompted. The display system may be configured to prompt the user to perform complex combinations of movements and determine whether the user successfully completed these movements and / or the extent to which the user was able to at least partially complete the commands.

[0250] 11 , the systems and sensors described herein may perform method 1700 to detect and / or diagnose a neurological disorder associated with apraxia in a user. In block 1710, a display system may be configured to provide commands and perform a sequence of body or body part movements. For example, a user may be prompted to mimic a hand gesture or mimic the use of a tool. As another example, a user may be prompted to pretend to brush their teeth or pretend to comb their hair. In an embodiment, the display device may prompt a user to perform gestures that interact with physical and / or virtual objects (e.g., using a tool).

[0251] 11 , the display system may detect a user's response to the stimulus, which is indicative of the user's ability to perform the prompted skill movement. In some embodiments, the display system may be configured to image or otherwise detect the position and movement of the user's hand and / or any object with which the user interacts. Additionally, in some embodiments, the display system may be configured to sense the user's eye gaze, the user's eye focus, or the elapsed time from the initiation of a stimulus (e.g., prompting the user) to the user's response to the stimulus.

[0252] In block 1730, the display system may be configured to determine whether the user is suffering from apraxia and to what extent. In some embodiments, the display system may determine that the user was unable to complete the prompted skill exercise.

[0253] In some embodiments, the display system may perform a baseline test to confirm that the user does not have a motor or language disorder. For example, the display system may perform block 1710 by prompting the user to perform a simple movement, sense the user's movement in response to the prompt in block 1720, and determine whether the prompted movement was successfully completed in block 1740. If the movement is successfully completed, the system may subsequently perform blocks 1710, 1720, and 1730, which involve a more complex sequence of movements, as described above. If, on subsequent tests, the display system determines that the user's movements are awkward and only slightly similar to those prompted by the display system (even though the user may have full acquisition or otherwise normal motor control as evidenced by previous tests with simple movements), the display system may be configured to conclude that apraxia exists in the user. In some embodiments, the display system may determine that the user completes the prompted skill movement slowly and / or only partially completes the movement, which may also be indicative of apraxia.

[0254] In response to determining that apraxia is present, the display system may be configured to provide notification of the presence and / or extent of the apraxia and of a possible disease or injury causing the apraxia. Examples of possible diseases or injuries include Gerstmann's syndrome, Huntington's disease, corticobasal degeneration, and stroke.

[0255] 12 , the systems and sensors described herein may be used according to method 1800 for therapy applications. At block 1810, in some embodiments, a stimulus directed at a user, such as those described above with reference to the responses in FIG. 11 , may be sensed or detected. For example, the display system may be configured to monitor the user's daily habits, routines, and physical activities, in part by using environmental sensors 34 or other sensors. At block 1820, in some embodiments, the display system may determine that the stimulus is associated with apraxia.

[0256] As in the discussion regarding agnosia above, in some embodiments, the display system can be configured to interact with other systems, objects, totems, units, or items as described herein to provide therapy for apraxia (e.g., clothing, processors, TENS / EMS / PMS units). In an embodiment, the display system can be configured to use such systems, objects, totems, units, or items to initiate sensations (e.g., tactile sensations) and / or stimuli (e.g., electrical, mechanical, thermal, biochemical) as described herein. In some embodiments, the provided stimuli can provide many benefits as described herein.

[0257] The display system may also be configured to display sensory aids for apraxia in block 1830. For example, the displa...

Claims

1. 1. A display system, comprising: a head-mounted display comprising one or more waveguides configured to display augmented reality image content by projecting light to a user, the one or more waveguides further configured to transmit light from a surrounding environment to the user and to display one or more virtual contents; one or more inward-facing cameras, the one or more inward-facing cameras positioned to image one or more eyes of the user; one or more processors; one or more computer storage media storing instructions; Equipped with The instructions, when executed by the one or more processors, determining one or more abnormalities by tracking eye movements of the user based on imaging data received from the one or more inward-facing cameras, wherein the tracked eye movements are involuntary eye movements including at least one of lateral shifts of the eyes or upward rolls of the eyes, and the one or more abnormalities are abnormal oscillations or repetitive uncontrollable movements of the one or more eyes of the user caused by nystagmus, and determining the one or more abnormalities is determining nystagmus from the tracked eye movements; causing the head mounted display to display the one or more virtual contents in response to the nystagmus, the one or more virtual contents being configured to move in synchronization with the involuntary eye movement; a display system that causes the one or more processors to perform operations including:

2. the one or more processors: determining a response of the user to the provided one or more pieces of virtual content; triggering a sensory aid based on the determined response; and The display system of claim 1 , further configured to perform operations including:

3. the one or more processors: monitoring the condition of the nystagmus daily for several days; automatically repeating the displaying of the one or more virtual contents on the head mounted display multiple times each day; The display system of claim 1 , further configured to perform operations including:

4. 10. The display system of claim 1, wherein the one or more processors are further configured to perform operations including providing an alert to the user that the one or more virtual contents are being provided.

5. The display system of claim 1 , wherein the tracked eye movements further include pupil movement due to the nystagmus.

6. 6. The display system of claim 5, wherein the one or more virtual contents include an image, and the image on the head-mounted display is moved by an amount that is less than the amplitude of pupil movement caused by the nystagmus.

7. 1. A method of operating a display system, the display system comprising: one or more processors; one or more inward-facing cameras; and a head-mounted augmented reality display; The method comprises: the head-mounted augmented reality display displaying one or more virtual contents; the one or more processors tracking eye movements of the user, wherein the one or more processors tracking the eye movements of the user includes determining one or more abnormalities by receiving imaging data from the one or more inward-facing cameras of the display system, the tracked eye movements being involuntary eye movements including at least one of lateral shifts of the eyes or upward rotations of the eyes, the one or more abnormalities being abnormal oscillations or repetitive uncontrollable movements of the one or more eyes of the user due to nystagmus, and determining the one or more abnormalities is the one or more processors determining nystagmus from the tracked eye movements; the one or more processors cause the head-mounted augmented reality display to display the one or more virtual contents in response to the nystagmus, the one or more virtual contents being configured to move in synchronization with the involuntary eye movement; A method comprising:

8. The method comprises: the one or more processors monitoring the nystagmus condition daily over several days; the one or more processors automatically repeat causing the head-mounted augmented reality display to display the one or more virtual contents multiple times each day; The method of claim 7 further comprising:

9. The method of claim 7 , further comprising the one or more processors providing an alert to the user that the one or more pieces of virtual content are being provided.

10. The method of claim 7 , wherein the tracked eye movements further include pupil movement due to nystagmus.

11. The method of claim 10 , wherein the one or more virtual contents include an image, and the image is moved by an amount that is less than the amplitude of pupil movement due to rotational nystagmus.

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