Systems and methods for cueing the recall of specific memories during wakefulness

Abstract

Describes a system for cueing specific memories in a waking state. The system sends an initiation signal to a memory recall controller to select a stored stimulus pattern previously associated with a specific memory of an event. The system signals the memory recall controller to initiate delivery of the selected stimulus pattern to the waking brain via a brain stimulation system during the duration of the event. After the event is completed, the system signals the memory recall controller to block delivery of the selected stimulus pattern by the brain stimulation system.

Description

[0001] Government licensing rights

[0002] This invention was made with government support under government contract number DARPA BTO W911NF-16-C-0018. The government has certain rights in the invention.

[0003] Cross-reference to related applications

[0004] This is a partial continuation application of U.S. application No. 15 / 332,787, filed in the United States on October 24, 2016, entitled "Method and System to Accelerate Consolidation of Specific Memories Using Transcranial Stimulation", which is a non-provisional patent application of U.S. Provisional Application No. 62 / 245,730, filed in the United States on October 23, 2015, entitled "Method and System to Accelerate Consolidation of Specific Memories Using Transcranial Stimulation", the entire content of which is incorporated herein by reference.

[0005] This is a partial continuation application of U.S. Application No. 15 / 990,460, entitled "Targeted Steerable Transcranial Intervention to Accelerate Memory Consolidation", filed in the United States on May 25, 2018. U.S. Application No. 15 / 990,460 is a partial continuation application of U.S. Application No. 15 / 332,787, filed in the United States on October 24, 2016. U.S. Application No. 15 / 332,787 is a non-provisional patent application of U.S. Provisional Application No. 62 / 245,730, filed in the United States on October 23, 2015, the entire content of which is incorporated herein by reference. U.S. Application No. 15 / 990,460 is also a partial continuation application of U.S. Application No. 15 / 227,922, filed in the United States on August 3, 2016 and published as U.S. Patent No. 10,092,753 on October 9, 2018. U.S. Application No. 15 / 227,922 is a non-provisional patent application of U.S. Provisional Patent Application No. 62 / 210,907, entitled "Method to Enhance Specific Memories with tCS During Slow-Wave Sleep", filed in the United States on August 27, 2015, U.S. Provisional Application No. 62 / 210,890, entitled "Transcranial Intervention to Weaken Traumatic Memories", filed in the United States on August 27, 2015, and U.S. Provisional Application No. 62 / 247,435, entitled "Mapping Transcranial Signals to Transcranial Stimulation Required to Reproduce a Brain State", filed in the United States on October 28, 2015, the entire content of which is incorporated herein by reference. U.S. Application No. 15 / 990,460 is also a partial continuation application of U.S. Application No. 15 / 947,733, filed in the United States on April 6, 2018. U.S. Application No. 15 / 947,733 is a non-provisional patent application of U.S. Provisional Application No. 62 / 516,350, filed in the United States on June 7, 2017, the entire content of which is incorporated herein by reference.U.S. Application No. 15 / 947,733 is a partial continuation application of U.S. Application No. 15 / 332,787, filed in the United States on October 24, 2016, entitled "Method and System to Accelerate Consolidation of Specific Memories Using Transcranial Stimulation". U.S. Application No. 15 / 332,787 is a non-provisional patent application of U.S. Provisional Application No. 62 / 245,730, filed in the United States on October 23, 2015, entitled "Method and System to Accelerate Consolidation of Specific Memories Using Transcranial Stimulation", the entire content of which is incorporated herein by reference. U.S. Application No. 15 / 947,733 is a partial continuation application of U.S. Application No. 15 / 583,983, filed in the United States on May 1, 2017, entitled "System and Method for Neurostimulation-Enhanced Second Language Acquisition". U.S. Application No. 15 / 583,983 is a non-provisional patent application of U.S. Provisional Application No. 62 / 330,440, filed on May 2, 2016, entitled "A Method for Neurostimulation-Enhanced Second Language Acquisition", the entire content of which is incorporated herein by reference. U.S. Application No. 15 / 990,460 is also a non-provisional patent application of U.S. Provisional Application No. 62 / 570,669, filed in the United States on October 11, 2017, U.S. Provisional Application No. 62 / 558,133, filed in the United States on September 13, 2017, and U.S. Provisional Application No. 62 / 537,892, filed in the United States on July 27, 2017, the entire content of which is incorporated herein by reference.

[0006] This is also a non-provisional application of U.S. Provisional Application No. 62 / 681,503, filed in the United States on June 6, 2018, entitled "System and Method to Cue Specific Memory Recalls While Awake", the entire content of which is incorporated herein by reference. Technical Field

[0007] The present invention relates to a system for cueing the recall of a specific memory, and more particularly, to a system for cueing the recall of a specific memory by associating a stimulus pattern with the memory during a waking experience and subsequently evoking the recall of the memory during waking by applying the same stimulus pattern. Background Art

[0008] In operational tasks such as commercial and educational scenarios, it is crucial to rapidly integrate and accurately recall memories based on limited information exposure. One simple way to evoke the recall of a specific memory is to have a person or an automated system send a reminder (e.g., a calendar reminder). The reminder must describe the memory in sufficient detail to evoke the memory recall. However, in cases where the memory is subtle and not easily described, such a reminder may not be practical. For example, a procedural skill such as how to execute a tennis serve is a coordinated choreography of movements, and a student practices it with a teacher. At some point, the teacher may announce that the student has executed the serve correctly, but the serve must be practiced many times to "internalize" it. For such a memory, simple descriptors are too indirect; they cannot capture the complex sensations of a complex task such as executing a serve.

[0009] In state-of-the-art laboratory experiments, auditory or olfactory cues are associated with a simplified laboratory task during execution (such as remembering the position of icons on a two-dimensional (2D) grid), and then these cues are used during sleep to trigger the replay of the task execution memory, thereby consolidating the memory during sleep. This has been shown to result in improved behavioral performance during the next waking period (see the incorporated list of literature references, see References 1, 2, 3). However, these cues have not been used to trigger memory recall during the waking period, and in any case, they are not practical for operational use during the waking period because they may be lost in a complex surrounding environment, and the number of such cues with unique discriminability is limited. Additionally, in the prior art, drugs are generally also used to improve memory (see reference documents 4 and 5), but they cannot selectively enhance specific memories.

[0010] Accordingly, there is a continuing need for a system for memory reactivation that can be used to cue the recall of a specific memory when needed during waking. Summary of the Invention

[0011] The present invention relates to a system for cueing the recall of specific memories, and more particularly, to a system for cueing the recall of specific memories by associating a stimulus pattern with a memory during a waking experience and subsequently evoking the recall of the memory during waking by applying the same stimulus pattern. The system includes a non-transitory computer-readable medium encoded with executable instructions such that when the executable instructions are executed, one or more processors perform a plurality of operations. The system sends an initiation signal to a memory recall controller to select a stored stimulus pattern previously associated with a specific memory of an event. The memory recall controller is caused to initiate the transmission of the selected stimulus pattern to the waking brain via a brain stimulation system during the duration of the event. After the event is completed, the system signals the memory recall controller to block the transmission of the selected stimulus pattern by the brain stimulation system.

[0012] In another aspect, the initiation signal is generated by one of a user and an external automated system.

[0013] In another aspect, the stored stimulus pattern includes at least one event descriptor corresponding to a salient feature of the event, and the external automated system tracks salient features of the user's environment and actions such that when the salient features match the at least one event descriptor, the external automated system generates the initiation signal.

[0014] In another aspect, the system generates the stored stimulus pattern as follows. When the user is to experience a new event for recall at a later time, the system sends an initiation signal to the memory recall controller to select a unique stimulus pattern. The memory recall controller is caused to initiate the transmission of the unique stimulus pattern to the brain via the brain stimulation system during the duration of the new event. After the new event is completed, the system signals the memory recall controller to block the transmission of the unique stimulus pattern by the brain stimulation system. The unique stimulus pattern is stored together with at least one event descriptor of the new event.

[0015] In another aspect, the system provides instructions for relaxation to the user before causing the memory recall controller to initiate the transmission of the selected stimulus pattern.

[0016] In another aspect, the system is configured to receive feedback from the user that the user is ready to receive the transmission of the selected stimulus pattern.

[0017] In another aspect, the brain stimulation system includes a neurocap having one or more electrodes.

[0018] In another aspect, the transmission of the selected stimulus pattern is initiated based on a detected change in position via Global Positioning System (GPS) coordinates.

[0019] In another aspect, the new event is the recognized driving situation, and the delivery of the unique stimulation pattern evokes the recollection of appropriate skills to handle the recognized driving situation.

[0020] Finally, the present invention also includes a computer program product and a computer-implemented method. The computer program product includes computer-readable instructions stored on a non-transitory computer-readable medium, which are executed by a computer having one or more processors such that, when the instructions are executed, the one or more processors perform the operations listed herein. Alternatively, the computer-implemented method includes the act of causing a computer to execute such instructions and perform the resulting operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The objects, features, and advantages of the present invention will become apparent from the following detailed description of various aspects of the present invention in conjunction with the following drawings, in which:

[0022] Figure 1 is a block diagram depicting components of a system for prompting the recollection of specific memories according to some embodiments of the present disclosure;

[0023] Figure 2 is an illustration of a computer program product according to some embodiments of the present disclosure;

[0024] Figure 3 is an illustration of a system flow for prompting specific memories while a user is awake according to some embodiments of the present disclosure;

[0025] Figure 4 is an illustration of a memory recollection controller flow during training according to some embodiments of the present disclosure;

[0026] Figure 5 is an illustration of a memory recollection controller flow during recollection according to some embodiments of the present disclosure; and

[0027] Figure 6 is an illustration of a human subject receiving neural stimulation via a neural device according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0028] The present invention relates to a system for cueing the recall of specific memories, and more particularly, to a system for cueing the recall of specific memories by associating a stimulus pattern with a memory during a waking experience and subsequently evoking the recall of the memory during waking by applying the same stimulus pattern. The following description is presented to enable a person of ordinary skill in the art to make and use the invention and to incorporate it into the context of a particular application. Various modifications and various uses in different applications will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to a wide variety of aspects. Thus, the present invention is not intended to be limited to the aspects presented, but rather to cover the broadest scope consistent with the principles and novel features disclosed herein.

[0029] In the following detailed description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without limitation to these specific details. In other instances, well-known structures and devices are shown in block diagram form rather than in detail in order to avoid obscuring the present invention.

[0030] The reader is cautioned to note all documents and files that are concurrently filed with this specification and that are publicly available for inspection with this specification, and the contents of all such documents and files are hereby incorporated by reference. All features disclosed in this specification (including any appended claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is only an example of a general series of equivalent or similar features.

[0031] Furthermore, any element in a claim that does not expressly state "means for" performing a specified function or "step for" performing a particular function is not to be construed as a "means" or "step" clause as specified in 35 U.S.C. § 112, ¶ 6. In particular, the use of "step of" or "act of" in the claims herein is not intended to invoke the provisions of 35 U.S.C. § 112, ¶ 6.

[0032] Before the present invention is described in detail, a list of cited references is first provided. Next, a description of the various main aspects of the present invention is provided. Finally, specific details of the various embodiments of the present invention are provided to give an understanding of the specific aspects.

[0033] (1) List of incorporated references

[0034] The following references are cited and incorporated into this application. For clarity and convenience, these references are listed here as a central resource for the reader. The following references are incorporated herein by reference as if fully set forth herein. These references are cited in this application by reference to the corresponding reference numbers as follows:

[0035] 1. Rudoy JD, Voss JL, Westerberg CE, Paller KA. Strengthening Individual Memories by Reactivating Them During Sleep. Science. 2009 Nov 20; 326(5956): 1079-1079.

[0036] 2. Diekelmann S, Biggel S, Rasch B, Born J. Offfline consolidation of memory varies with time in slow wave sleep and can be accelerated by cuing memory reactivations. Neurobiol Learn Mem. 2012 Sep; 98(2): 103-11.

[0037] 3. Rasch B, Buchel C, Gais S, Born J. Odor cues during slow-wave sleep prompt declarative memory consolidation. Science. 2007; 315(5817): 1426-9.

[0038] 4. Rasch BH, Born J, Gais S. Combined blockade of cholinergic receptors shifts the brain from stimulus encoding to memory consolidation. J Cogn Neurosci. 2006 May; 1 8(5): 793-802.

[0039] 5. Gais S, Born J. Low acetylcholine during slow-wave sleep is critical for declarative memory consolidation. Proc Natl Acad Sci U S A. 2004 Feb 17;101(7):2140-4.

[0040] (2) Main aspects

[0041] Each embodiment of the present invention includes three "main" aspects. The first main aspect is a system for cueing the recall of specific memories during wakefulness. The system generally takes the form of computer system operating software or a "hard-coded" instruction set. The system can be incorporated into a wide variety of devices that provide different functions. The second main aspect is a method generally in the form of software that runs on a data processing system (computer). The third main aspect is a computer program product. The computer program product generally represents computer-readable instructions stored on a non-transitory computer-readable medium such as an optical storage device (e.g., a compact disc (CD) or a digital versatile disc (DVD)) or a magnetic storage device (such as a floppy disk or a magnetic tape). Other non-limiting examples of computer-readable media include hard disks, read-only memories (ROMs), and flash-type memories. These aspects will be described in more detail below.

[0042] Figure 1 A block diagram is provided showing an example of the system of the present invention (i.e., computer system 100). Computer system 100 is configured to perform computations, processes, operations, and / or functions associated with a program or algorithm. In one aspect, certain processes and steps discussed herein are implemented as a series of instructions (e.g., a software program) residing within a computer-readable memory unit and executed by one or more processors of computer system 100. When executed, these instructions cause computer system 100 to perform specific actions and exhibit specific behaviors, such as those described herein.

[0043] Computer system 100 may include an address / data bus 102 configured to transfer information. Additionally, one or more data processing units (such as processor 104 (or processors)) are coupled to address / data bus 102. Processor 104 is configured to process information and instructions. In one aspect, processor 104 is a microprocessor. Alternatively, processor 104 may be a different type of processor, such as a parallel processor, an application-specific integrated circuit (ASIC), a programmable logic array (PLA), a complex programmable logic device (CPLD), or a field-programmable gate array (FPGA).

[0044] The computer system 100 is configured to utilize one or more data storage units. The computer system 100 may include a volatile memory unit 106 (e.g., random access memory (“RAM”), static RAM, dynamic RAM, etc.) coupled to an address / data bus 102, where the volatile memory unit 106 is configured to store information and instructions for the processor 104. The computer system 100 may also include a non-volatile memory unit 108 (e.g., read only memory (“ROM”), programmable ROM (“PROM”), erasable programmable ROM (“EPROM”), electrically erasable programmable ROM (“EEPROM”), flash memory, etc.) coupled to the address / data bus 102, where the non-volatile memory unit 108 is configured to store static information and instructions for the processor 104. Alternatively, the computer system 100 may execute instructions retrieved from an online data storage unit such as in “cloud” computing. In one aspect, the computer system 100 may also include one or more interfaces (such as interface 110) coupled to the address / data bus 102. The one or more interfaces are configured to enable the computer system 100 to interface with other electronic devices and computer systems. The communication interfaces implemented by the one or more interfaces may include wired communication technologies (e.g., serial cable, modem, network adapter, etc.) and / or wireless communication technologies (e.g., wireless modem, wireless network adapter, etc.).

[0045] In one aspect, the computer system 100 may include an input device 112 coupled to the address / data bus 102, where the input device 112 is configured to transfer information and command selections to the processor 100. According to one aspect, the input device 112 is an alphanumeric input device (such as a keyboard) that may include alphanumeric keys and / or function keys. Alternatively, the input device 112 may be an input device other than an alphanumeric input device. For example, a system initiation signal 310 may be initiated from a button in a convenient location on the body by a wireless interface, much like a smartwatch. In one aspect, the computer system 100 may include a cursor control device 114 coupled to the address / data bus 102, where the cursor control device 114 is configured to transfer user input information and / or command selections to the processor 100. In one aspect, the cursor control device 114 is implemented using a device such as a mouse, trackball, touchpad, optical tracking device, or touchscreen. Nevertheless, in one aspect, the cursor control device 114 is directed and / or activated by input from the input device 112, such as in response to using special keys and key sequence commands associated with the input device 112. In an alternative aspect, the cursor control device 114 is configured to be directed or guided by voice commands.

[0046] In one aspect, computer system 100 may further include one or more optional computer-usable data storage devices (such as storage device 116) coupled to address / data bus 102. Storage device 116 is configured to store information and / or computer-executable instructions. In one aspect, storage device 116 is a storage device such as a magnetic or optical disk drive (e.g., hard disk drive (“HDD”), floppy disk, compact disc read-only memory (“CD-ROM”), digital versatile disc (“DVD”)). According to one aspect, display device 118 is coupled to address / data bus 102, wherein display device 118 is configured to display video and / or graphics. In one aspect, display device 118 may include a cathode ray tube (“CRT”), liquid crystal display (“LCD”), field emission display (“FED”), plasma display, or any other display device suitable for displaying video and / or graphic images as well as user-recognizable alphanumeric characters.

[0047] The computer system 100 presented herein is an example computing environment according to one aspect. However, non-limiting examples of computer system 100 are not strictly limited to being a computer system. For example, one aspect provides that computer system 100 represents data processing analysis that may be used according to the various aspects described herein. Additionally, other computing systems may be implemented. In fact, the spirit and scope of the present technology are not limited to any single data processing environment. Thus, in one aspect, one or more operations of the present technology are controlled or implemented using computer-executable instructions (such as program modules) executed by a computer. In one implementation, such program modules include routines, programs, objects, components, and / or data structures configured to perform particular tasks or implement particular abstract data types. Additionally, one aspect provides for implementing one or more aspects of the present technology by leveraging one or more distributed computing environments, such as in a distributed computing environment where tasks are performed by remote processing devices linked by a communication network, or such as in a distributed computing environment where various program modules are located in local and remote computer storage media including memory-storage devices.

[0048] Figure 2A diagram showing a computer program product (i.e., a storage device) embodying the present invention is shown. The computer program product is shown as a floppy disk 200 or an optical disk 202 such as a CD or a DVD. However, as previously mentioned, the computer program product generally represents computer-readable instructions stored on any compatible non-transitory computer-readable medium. The term "instructions" as used with respect to the present invention generally indicates a set of operations to be performed on a computer and can represent a fragment of an entire program or a single separable software module. Non-limiting examples of "instructions" include computer program code (source or object code) and "hard-coded" electronics (i.e., computer operations encoded into a computer chip). The "instructions" are stored on any non-transitory computer-readable medium, such as in the memory of a computer or on a floppy disk, a CD-ROM, and a flash drive. In either case, these instructions are encoded on the non-transitory computer-readable medium.

[0049] (3) Specific details of various embodiments

[0050] In operating tasks (in many commercial and educational scenarios), it is crucial to quickly integrate and accurately recall memories based on limited information exposure. The invention described herein prompts the recall of specific memories during wakefulness. Once a memory is consolidated in long-term memory, it can resist decay and can be recalled days, months, or years later. However, previously, it was not possible to selectively recall one memory over another, whether consolidated or not. As described in detail below, the system according to embodiments of the present disclosure will, when needed, prompt the recall of a specific memory at a certain time after experiencing the specific memory during wakefulness. Specifically, the system applies a unique electrical or magnetic stimulation pattern to the brain in a wakeful state to prompt the recall of a memory previously associated with the same pattern. The number of unique patterns that can be generated is limited by the number of stimulation sites, and thus a large number of sites (referred to as high definition) may be required. Alternatively, U.S. Patent Publication No. 2018 / 0272129, which is incorporated herein by reference as if fully set forth herein, teaches a method that uses an interference pattern between a small number of electrodes to move the pattern over time; such temporal movement can be used to generate high-definition patterns with a smaller number of electrodes.

[0051] The following is a description from U.S. Application No. 15 / 332,787, which is incorporated herein by reference, and which describes the application of memory consolidation and stimulation. Memories to be consolidated are tagged by associating the memory with a cue. However, the system applies a unique transcranial current stimulation (tCS) montage rather than sounds or smells, the transcranial current stimulation (tCS) montage including a spatio-temporal amplitude modulation pattern (STAMP) of currents on sensory and associative cortical sites during different experiences or skill learning. Generally speaking, STAMP can be any spatial, temporal, or spatio-temporal pattern of transcranial current on the scalp through multiple channels, each channel being applied to a different site on the scalp. The advantage of the STAMP method according to an embodiment of the present disclosure is that it does not degrade task performance or distract from the learning task. STAMP tagging does not need to compete with environmental noise or smells, and more unique patterns can be achieved using STAMP. In addition, transcranial current stimulation (tCS) can be applied to the prefrontal cortex (PFC) during specific encoding to strengthen memory formation and increase the likelihood and fidelity of subsequent replay.

[0052] STAMP is a weighted spatio-temporal function and can be naturally instantiated using a variety of endogenous brain rhythms (theta frequency, slow gamma frequency, and fast gamma frequency), which typically occur during the execution of attention tasks throughout the brain. tCS applies STAMP on the scalp. Additionally, during an experience event, tDCS (DC transcranial stimulation) can be used on the PFC to enhance encoding strength as a means of increasing the probability of memory replay during subsequent offline periods. Furthermore, the method according to various embodiments of the present invention is agnostic to stimulation techniques and can also be implemented by transcranial magnetic stimulation (TMS). In addition, electromagnetic STAMP can be combined with unique sensory cues (e.g., auditory or olfactory) to further achieve an unprecedented level of target memory tagging and cueing. Finally, the system can be implemented using currently commercially available technologies (e.g., Neuroelectrics 32-channel tCS; EGI 128-channel tCS) and can be integrated into a portable system.

[0053] The STAMP tag is applied to the brain using electrical stimulation (e.g., tCS, tDCS) and stored (e.g., in a data storage drive). A STAMP stimulation montage can be created without reference to endogenous rhythms, simply by applying a unique set of DC or AC currents to multiple electrodes on the scalp. In one embodiment, the cumulative average amplitude of the STAMP on the scalp will be approximately 2 milliamperes (mA). Those skilled in the art can experiment with different values to find the optimal STAMP that is strong enough to "tag" memories without unduly affecting them. Transcranial magnetic stimulation, or auditory or olfactory stimulation, can also be used to create STAMP tags in a similar manner. These are alternative ways to associate unique patterns with the memories to be recalled.

[0054] Figure 3 A system including a brain stimulation system 300 and a memory recall controller 302 is shown. As described above, a suitable brain stimulation system 300 is disclosed in U.S. Application No. 15 / 332,787. In one embodiment, the brain stimulation system 300 is high-definition transcranial current stimulation (HD-tCS), which can be an AC (alternating current) or DC (direct current) system. The essential property of the stimulation is that it can deliver a unique pattern to the brain 304. The higher the resolution of the stimulation, the more unique stimulation patterns 306 the pattern generator can generate, which is a priori offline process not specific to any particular individual. Pattern generation is done iteratively. A set of maximally uncorrelated stimulation pattern vectors is generated, specifying the stimulation levels to be applied to the respective locations on the scalp, and ensuring that the maximum current applied to any electrode and the total current passing through all electrodes are within a safe range.

[0055] The pattern generator can be most simply implemented by creating a normalized vector of random numbers (one normalized vector per stimulation electrode), and then multiplying by the total amount of stimulation to be applied (default is 2 mA). The result must be adjusted so that the electrodes do not provide more than a safe amount of current (e.g., default value is 1 mA). Most desirably, the generated patterns are maximally different from any other patterns created, so that each pattern cues a particular memory rather than others. One way is to place the set of generated vectors as columns in a matrix A. Then, the matrix is reduced to row echelon form B using Gaussian elimination. The columns of B that contain the leading term 1 (pivots) are the columns of A that form a maximally linearly independent vector set. The other columns are removed and replaced with random vectors generated using the above process, and Gaussian elimination is repeated to achieve linear independence until all vectors are maximally uncorrelated. Examples of suitable pattern generators are also described in U.S. Application No. 15 / 332,787.

[0056] When encoding a memory (i.e., when an event occurs and the user is experiencing the event, forming the memory), the memory recall controller 302 turns on the application of the stimulus (power-on / off mode 308) in a unique stimulus pattern. This stimulus pattern is associated with the memory because cortical stimuli (such as sensory activities) are all connected to cortical regions that project to the hippocampus (the location of episodic memories in the brain). During subsequent waking experiences, which may be hours, days, or even possibly months later, when the user needs help to recall that specific memory, the system initiates a signal 310 to induce the memory recall controller 302 to retrieve the same pattern associated with that memory when the memory was first encoded and apply that pattern to the brain 304 again, thereby prompting the recall of the memory.

[0057] On the other hand, the stimulus pattern includes a transcranial electrical stimulation pattern to be applied to one or more electrodes (the one or more electrodes to be applied to the scalp), or a transcranial magnetic stimulation (TMS) pattern, or an auditory or olfactory or other type, or a combination of these types. Additional signals may be undesirable or unnecessary, but if added, they can enhance memory-related cues according to the application. However, odors and sounds are limited by human sensory acuity, and the sensory acuity can vary greatly from person to person, especially among certain challenging populations (such as the elderly or those with cognitive deficits). In some environments (such as noisy, windy, or odor-filled environments, such as some military combat environments), it is also difficult to distinguish odors. TMS and HD-tCS bypass the senses and directly stimulate the cortex.

[0058] In experimental studies conducted on more than 100 human subjects, it was found that a 2mA HD tCS stimulus pattern diffused across 64 or 128 electrodes (where the current delivered by the electrodes does not exceed 1mA) was well tolerated and could appropriately label the memory for later recall. These studies also used the STAMP stimulus pattern to be associated with the memory during encoding, but different from the invention described herein, to enhance memory consolidation, the memory was cued during sleep and a behavioral recall test was conducted during the subsequent daytime period without stimulation. The present invention does not operate at all during sleep, but only indirectly enhances memory consolidation, as described above, and reapplies the stimulus pattern during the subsequent waking time to cue the memory. In addition, different from the prior art, the invention described herein is an open-loop application and does not require application at a specific frequency or stage of consciousness. Experimental studies have indeed confirmed the safety of the STAMP protocol and its ability to affect memory. A database 306 is pre-prepared with stimulus patterns designed to be maximally unique, and the pattern can be selected by the memory recall controller 302 from this database. The database includes a list of unique patterns that have been previously generated and stored and have not yet been associated with memories.

[0059] Once a set of patterns is available, one pattern can be randomly selected when a memory needs to be "tagged". When a pattern is selected, it is removed from the pool of available patterns, and the pattern is stored along with a description of the memory associated with that pattern (during the encoding process). The description can take the form of a set of semantic tags that describe the memory, such as "tennis serve" or "parallel parking". In practice, it is preferable to provide semantic tags with reference to an ontology that identifies the context, such as "vehicle - operation" / "automobile" / "parking" / "parallel". Such a semantic tagging scheme may be general, and the same stimulus pattern may be used for different subjects. However, for an individual, each stimulus pattern must be unique.

[0060] Figure 4 is a flowchart depicting the flow of the memory recall controller 302 during training (i.e., during memory encoding). When not in operation, the stimulation system 300 is idle (400) and waits for power - on, which is applied in response to an initiation signal. The system initiation signal 310 can be a user - initiated signal 402 or an external - system - initiated signal 404, such as a change in position detected via GPS coordinates. At initiation, when the user is about to experience a new significant event, the memory recall controller 302 selects a unique stimulus pattern and induces the stimulation system 300 to apply 406 that unique stimulus pattern. A particular stimulation system may have a specialized way to command it, but each system should have a roughly equivalent way to specify the stimulation command to apply a vector of stimulation intensity to a set of electrodes and to stop the stimulation as commanded. Non - limiting examples of significant events to be remembered are a series of steps such as how to perform cardiopulmonary resuscitation (CPR), complex and critical steps in a military raid mission rehearsal, a tennis serve, some phases of vehicle operation, or steps in a factory manufacturing task. When the training event starts, the memory recall controller 302 turns on the stimulation system 300 to apply the selected unique pattern (element 406). As described above, this can be initiated by the user (element 402) or an external training system (element 404). When the event / task ends 408, similarly, a signal is sent to the memory recall controller 302 to stop the intervention (element 410) by turning off the stimulation system 300 and storing the pattern along with the characteristic features of the event (i.e., the event descriptor) for later use.

[0061] Figure 5Depicts the flow of the memory recall controller 302 during recall (i.e., when the user needs assistance in recalling a memory). At some subsequent time, perhaps hours, days, weeks, months, or even years later, when a particular memory needs to be recalled, the user (element 402) or an external support system (element 404) can assign to the stimulation system 300 the task of reapplying the same pattern (element 500) to prompt the recall of the memory. If possible, memory recall will be most effective if the user can assume a relaxed and quiet posture during the stimulation, so the system will ask, request, or provide instructions for the user to do so. The system can do this via a voice request, or if a display screen is available to the user, an icon or text request can be used. For best results, the user can close their eyes and count their breaths for the duration of the recall stimulation. If the user is in the middle of some attention-demanding task such as driving, they can pull over to the side of the road and stop briefly while the intervention is applied. This is a safety consideration for situations where the memory recall process might disorient the user. These are not necessary steps, but they can enhance the effectiveness of the intervention. When the user signals that they are ready to begin (i.e., provides feedback to the system) (element 502), the memory recall controller 302 activates the stimulation of the pattern for a period of time (i.e., the duration of the event), which is typically about 10 seconds, but can be about 1 second or about 100 seconds or about 1000 seconds, for example, to apply the pattern (element 504). The user can transmit this signal by clicking on an icon or text alert provided by the system, or the system can transmit this signal to the user by audibly commanding the user via a voice command system. After applying the stimulation, the stimulation system is idled (element 506).

[0062] Figure 6 Illustrates a human subject 600 receiving neural stimulation via a neural device 602. The neural device 602, which is capable of generating an electric current, performs neural stimulation via a neural stimulation assembly 604 (such as an HD-tCS stimulation electrode) that is in direct physical contact with the human subject 600. The neural stimulation assembly 604 can be part of a neural cap wearable by the human subject 600. Currently commercially available technology (e.g., the 32-channel HD-tCS from Neuroelectrics Corporation, Suite 201, 210 Broadway, Cambridge, MA 02139) can be plugged into a wall outlet, but some vendors are supplying portable devices that can be battery-powered. There are also wireless connections to stimulation caps, such as the Neuroelectrics Enobio32 system.

[0063] As described above, the memory recall controller 302 can initiate a stimulation event (element 406 or 504) as a result of a signal from a user (element 402) or from an external automated system (element 404). One use case is a training system for military mission exercises. When training in a virtual or physical model of the environment to be raided (as depicted in Figure 4 ), a soldier may face particularly difficult or complex parts of the mission, and when training (element 406) or practicing (element 504) that part of the mission, the memory recall controller 302 is turned on (element 402) to apply a unique pattern. During the original training session, a system according to an embodiment of the present disclosure can record the characteristics of the environment (which may include the precise global positioning system (GPS) coordinates of the location), along with the unique stimulation pattern. The environmental characteristics can be used as event descriptors to later access the appropriate pattern to be applied to recall the memory.

[0064] When a soldier is performing a mission, an automated system (element 404) external to the system described herein can track the soldier's progress, and when conditions (such as GPS coordinates, prominent features of the images around the soldier, etc.) match the stored location characteristics (such as GPS coordinates, features from previously captured images or from a model of that location, etc.), the system can automatically apply the stimulation pattern (element 504) previously associated with the memory of what was done at that location. For example, when a specific GPS coordinate is detected, the external automated system (element 404) can apply a stimulation pattern to help the soldier recall the previous scene and the locations of various elements in the scene, such as vehicles and buildings, as well as rooms, doors, and windows within the buildings. The automated system (element 404) can include multiple sensors for providing data related to the movement and location of the user, including but not limited to accelerometers, gyroscopes, magnetometers, GPS, and proximity sensors.

[0065] An alternative use case can be initiated entirely by the user. For example, if a new important event to be remembered is a sequence of steps such as CPR, the user can initiate a training phase (element 402) when the CPR technique is demonstrated (as shown in Figure 4 ). Then, at a later time, when CPR is needed but the user has forgotten some details (as shown in Figure 5As shown, the user can call up a pattern (element 402) in the pattern database using a keyword such as "CPR", and the system will apply the stimulation and the memory will be recalled (element 504). In one embodiment, the user needs to wear a neural cap with electrodes and needs to be at least wirelessly connected to a base station that will retrieve the stimulation pattern and control its application. In another embodiment, the components / parts of the neural device 602 are miniaturized and become more ergonomic. For example, the stimulation electrodes can be integrated into the cap or inserted into the user's skull, while the electronic device can be integrated into a mobile phone (or other mobile device) that is wirelessly connected to the electrodes to control the stimulation.

[0066] As described above, U.S. Application No. 15 / 332,787 describes a method that associates such a pattern with a memory during a waking experience and then uses the pattern during sleep to evoke memory consolidation, thus requiring sensing of brain signals to identify a specific sleep brain state and using closed-loop control at the frequency of slow-wave oscillations to apply stimulation. The system according to an embodiment of the present disclosure evokes the recall of such a memory during waking by applying a unique high-definition electrical or magnetic stimulation pattern to the brain during a quiet waking state when needed to prompt the recall of a memory previously associated with the same pattern. The present disclosure employs an open-loop application of stimulation and does not require sensing of the user's EEG during the training or subsequent use of the device. The waking memory reactivation technique is conceptually and operationally different from the above-described sleep consolidation method; it is simpler because it can operate in an open-loop manner (i.e., during a specific sleep stage, there is no need to coordinate the application with a specific phase of a specific concussion). It is only applied when waking recall is needed. Once the memory is consolidated into long-term memory, it does not decay and can be recalled days, months, or years later. The system will, when needed, during waking, at some point after the memory has been consolidated, prompt the recall of a specific memory.

[0067] If there are two similar memories, they will likely merge together when they are consolidated into long-term memory, and it will be difficult to extract one of them. The system according to an embodiment of the present disclosure can be used to prompt the most suitable version for the situation when needed based on the characteristics of the situation. For example, the prominent features of the situation can be used to prompt the correct version, such as parallel parking versus parking in a parking lot.

[0068] In addition, using the system described herein, the elderly with normal types of memory performance decline can improve the speed and accuracy of memory recall. Using the invention described herein, it is possible to assist people with certain memory deficits (e.g., Alzheimer's disease, dementia, or even traumatic brain injury) in recalling specific memories.

[0069] In addition, an automatic support system, such as a driver support system or a pilot-related system, can, where circumstances permit, initiate the recall of appropriate memories of the user by applying an appropriate stimulation pattern to the user. In a semi-autonomous driving system or a driver safety and support system, a system according to an embodiment of the present disclosure can be incorporated into the system to assist the driver in responding to the identified situation by evoking the driver's memory of how to handle such a situation. In this example, a driver training program can associate a unique stimulation pattern with each of a number of difficult situations, such as merging onto a highway or turning left into a side road. When the driver encounters one of these situations, their semi-autonomous driving system recognizes the situation and applies the associated pattern to the driver, evoking their memory of the appropriate skills for handling the situation. A car navigation system available on a mobile phone can recognize a left turn, or merging onto a highway. In addition, a pilot safety and support system can use the present invention in a similar manner as part of a pilot-related system.

[0070] In addition, during training, a soldier preparing to perform a task can associate a unique pattern with a particular complex part of the task and then, during the performance of the task, initiate the recall themselves to ensure clear and accurate performance. For example, if the system is running on a mobile phone, the user can initiate the system by saying "Recall X" or a similar voice command for identification. "Recall" would be the command to initiate the system described herein, and "X" would be a description for the system to locate the correct stimulation pattern. Finally, the invention described herein is useful for anyone attempting to remember the specific details of a process such as CPR. This is particularly valuable if the process was learned a long time ago and the memory, while consolidated, has become "stale" due to lack of use.

[0071] The advantages of a system according to an embodiment of the present invention can be explained by comparing it to alternatives that remind a user of a memory by describing some of its characteristics. This can be impractical. It may not be feasible to have a person who knows what memory is being attempted to be recalled, and an automated system may not be intelligent enough to know which characteristics would be appropriate cues. Even if such a reminder were available, the systems described herein would evoke the recall of the actual memory, which would be more vivid than a suggestion of the characteristics of the memory. In other words, the electrical stimulation montage will evoke a clear recollection of the original memory.

[0072] Finally, although the present invention has been described in accordance with multiple embodiments, those of ordinary skill in the art should readily recognize that the present invention can have other applications in other environments. It should be noted that there can be many embodiments and implementations. In addition, the appended claims are in no way intended to limit the scope of the present invention to the specific embodiments described above. Additionally, any use of the phrase "means for..." is intended to evoke a means-plus-function interpretation of an element and a claim, and any element that does not specifically use the phrase "means for..." should not be interpreted as a means-plus-function element, even if the claim otherwise includes the word "means". Further, although specific method steps have been stated in a particular order, these method steps can be performed in any desired order and fall within the scope of the present invention.

Claims

1. A system for cueing the recall of a specific memory during wakefulness, the system comprising: a non-transitory memory and one or more processors, the non-transitory memory encoded with instructions such that when the instructions are executed, the one or more processors perform the following operations: When a user will experience a new event for recall at a later time: In response to an initiation signal, randomly select a unique stimulus pattern; Initiate the transmission of the unique stimulus pattern to the brain via a brain stimulation system during the duration of the new event, thereby associating the unique stimulus pattern with a specific memory of the new event; After the new event is completed, prevent the brain stimulation system from transmitting the unique stimulus pattern; and Store the unique stimulus pattern together with at least one event descriptor of the new event and use it for recall at a later time, When a user needs help to recall the specific memory: In response to an initiation signal, select the stored unique stimulus pattern previously associated with a specific memory of an event; Initiate the transmission of the stored unique stimulus pattern to the awake brain via the brain stimulation system during the duration of the event; and After the event is completed, prevent the brain stimulation system from transmitting the stored unique stimulus pattern.

2. The system according to claim 1, wherein, the initiation signal is generated by one of a user and an external automated system.

3. The system according to claim 2, wherein, the stored unique stimulus pattern includes at least one event descriptor corresponding to a salient feature of the event, and wherein the external automated system tracks salient features of the user's environment and actions such that when the salient features match the at least one event descriptor, the external automated system generates the initiation signal.

4. The system according to claim 1, wherein, the one or more processors further perform the following operation: provide relaxation instructions to the user before initiating the transmission of the unique stimulus pattern.

5. The system according to claim 1, wherein, the one or more processors are configured to receive feedback from the user that the user is ready to receive the transmission of the unique stimulus pattern.

6. The system according to claim 1, wherein, the brain stimulation system includes a neurocap having one or more electrodes.

7. The system according to claim 1, wherein, the transmission of the selected stimulus pattern is initiated based on a detected change in position via Global Positioning System (GPS) coordinates.

8. The system according to claim 1, wherein, the new event is a recognized driving situation, and wherein the transmission of the unique stimulus pattern evokes the recall of appropriate skills to handle the recognized driving situation.

9. A computer program product for cueing the recall of a specific memory during wakefulness, the computer program product comprising: computer-readable instructions stored on a non-transitory computer-readable medium, the computer-readable instructions being executed by a computer having one or more processors to cause the processor to perform the following operations: When a user will experience a new event for later recall: In response to an initiation signal, a unique stimulation pattern is randomly selected; During the duration of the new event, initiate the transmission of the unique stimulation pattern to the brain via a brain stimulation system, thereby associating the unique stimulation pattern with a specific memory of the new event; After the new event is completed, prevent the brain stimulation system from transmitting the unique stimulation pattern; and Store the unique stimulation pattern together with at least one event descriptor of the new event and use it for recall at a later time, When the user needs assistance to recall the specific memory: In response to an initiation signal, select the stored unique stimulation pattern previously associated with a specific memory of an event; During the duration of the event, initiate the transmission of the stored unique stimulation pattern to the awake brain via the brain stimulation system; And After the event is completed, prevent the brain stimulation system from transmitting the stored unique stimulation pattern.

10. The computer program product according to claim 9, wherein, the initiation signal is generated by one of a user and an external automated system.

11. The computer program product according to claim 10, wherein, the stored unique stimulation pattern includes at least one event descriptor corresponding to a salient feature of the event, and wherein the external automated system tracks salient features of the user's environment and actions such that when the salient features match the at least one event descriptor, the external automated system generates the initiation signal.

12. The computer program product according to claim 9, wherein, the one or more processors further perform the following operation: provide relaxation instructions to the user before initiating the transmission of the unique stimulation pattern.

13. The computer program product according to claim 9, wherein, the one or more processors are configured to receive feedback from the user that the user is ready to receive the transmission of the unique stimulation pattern.

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