Autonomous device for evaluating the neurocognitive and physiological functions related to motion sickness and simulator sickness

Abstract

The invention relates to a portable, autonomous device for evaluating sensory and cognitive problems, characterised in that it comprises: - a processor configured to acquire and analyse real-time data; - an ECG module for capturing the user's heart rate variability (HRV) in response to sensory and cognitive stimuli; - an inertial measurement unit (IMU) comprising an accelerometer and a gyroscope, configured to detect and record the movements and posture of the user; - a capacitive touch screen for interaction with the user for carrying out standardised cognitive tests; - an integrated memory for storing the captured data and the programs; - a wireless connectivity module for transmitting the data to an external device; and in that the device is configured to perform, in real time, at least one evaluation of the impact of the disruptive sensory stimuli, including motion sickness and virtual-reality sickness, in uncontrolled environments.

Description

Autonomous device for the evaluation of neurocognitive and physiological functions related to motion sickness and simulator sickness. Scope of the invention

[0001] The present invention relates to the field of neurocognitive and physiological assessment devices, specifically oriented towards the detection and analysis of sensory disorders, such as motion sickness and cyber sickness.

[0002] Motion sickness and cybersickness are common sensory disorders linked to a desynchronization of sensory information received by the brain, particularly between the vestibular system (inner ear), visual signals, and proprioception. These disorders often result in symptoms such as nausea, dizziness, disorientation, and significant stress related to the anticipation of exposure to these disturbing environments.

[0003] Standardized cognitive tests, usually administered on computers or in clinical settings, have several limitations when applied to patients with sensory or cognitive impairments. The configuration of these systems, along with their lack of portability, prevents testing in real-world environments, which is particularly problematic for conditions like motion sickness, which often occurs during movement. Furthermore, computer-based devices do not allow for the simultaneous assessment of physiological responses, such as heart rate, oxygenation, or posture, which are crucial indicators in analyzing states of fatigue or disorientation.

[0004] This field is particularly concerned with portable and autonomous devices that allow for real-time assessment of the user's physiological and cognitive reactions in dynamic and uncontrolled environments.

[0005] It also touches on virtual and augmented reality technologies for the study of the effects of immersive visual stimuli and sensory conflicts, for applications in neuropsychology, cognitive ergonomics, and stress physiology.

[0006] Traditionally, neurocognitive and physiological tests to assess these disorders are conducted in clinical or laboratory settings, which limits their applicability in real-world and dynamic contexts. Furthermore, conventional assessment devices often rely on computers or fixed infrastructure and do not allow for real-time measurement of physiological or postural responses.

[0007] The invention is positioned as a portable solution, enabling assessments in natural and uncontrolled environments. By integrating sensors such as an ECG and an IMU (Inertial Measurement Unit), it offers a comprehensive and mobile analysis of physiological and cognitive responses to sensory disorders. This device aims to address the shortcomings of traditional assessment methods by providing a modular and autonomous solution, adapted to users' needs in diverse environments, whether on the go or in virtual reality. State of the art

[0008] "Modelling the Relationship Between Physiological Measures of Motion Sickness" is an academic thesis dedicated to the detection of motion sickness from physiological measurements, using machine learning techniques.

[0009] D1 describes an experimental protocol carried out on 40 adults exposed to simulations of vehicle journeys via a motion platform.

[0010] This measurement system is based on a Muse™ headband (EEG sensor + gyroscope), an ECG sensor (HR and HRV analysis), a skin conductance sensor (EDA), an Android device (10-inch Huawei tablet) for administering cognitive tests and machine learning algorithms (random forests, linear regressions) used to model the severity of motion sickness (Fast Motion Sickness Score – FMS) from the data collected.

[0011] We are also aware of US patent application US 2022 / 133212, which concerns a wearable well-being monitoring system designed to assess a user's cognitive state using head-worn devices. It employs sensors worn on a headband or helmet (motion sensors, EEG, etc.) and analyzes physiological signals (e.g., heart rate variability, alertness). Cognitive tests are administered via a connected terminal, such as a smartphone or computer. Data processing by a predictive model is performed remotely, potentially on a server or in the cloud. The results are displayed as a performance score or a cognitive fatigue alert. This system is intended for use in areas such as workplace alertness, road safety, and well-being monitoring, particularly for human operators in critical situations.

[0012] We are also familiar with US patent application 2023 / 140151 A1 (Rezai et al.), which describes a wearable and intelligent system for assessing mental and cognitive well-being, based on a set of physiological sensors (ECG, EEG, IMU, temperature, etc.) and a personalized algorithmic analysis. This system is designed to: Collect physiological data on the user via one or more wearable devices, including a wristband or a head-worn device; Continuously assess the user's state (stress level, alertness, focus, etc.); Generate a cognitive well-being score, via a personalized AI model, updated via

[0013] Transmit the data to an external terminal (e.g., smartphone) for display, further processing, or communication.

[0014] The invention focuses on monitoring general mental well-being, not specific sensory disorders. It never mentions the devitalization of larvae and is therefore not very relevant. Disadvantages of prior art

[0015] Prior art solutions require a computer and complex infrastructure to perform a comprehensive and standardized assessment of neurocognitive and physiological functions.

[0016] Laboratory tests do not always reflect the reality of individuals' everyday experiences. This introduces bias into the assessment, making diagnoses less accurate, particularly for dynamic disorders such as motion sickness, cybersickness, or stressful situations. Solution provided by the invention

[0017] To overcome these drawbacks, the present invention relates to a portable and self-contained device for the assessment of sensory and cognitive disorders, characterized in that it comprises: a processing unit configured for real-time data acquisition and analysis; an ECG module for capturing the user's heart rate variability (HRV) in response to sensory and cognitive stimuli; an inertial measurement unit (IMU) comprising an accelerometer and a gyroscope, configured to detect and record the user's movements and posture; a capacitive touchscreen for user interaction for the performance of standardized cognitive tests; integrated memory for storing captured data and programs; a wireless connectivity module for transmitting data to an external device;and in that the device is configured to perform in real time at least one assessment of the impact of disturbing sensory stimuli, including motion sickness and cybersickness, in uncontrolled environments.

[0018] According to specific implementation methods:

[0019] The ECG module is configured to analyze heart rate variability (HRV) by detecting indicators of physiological stress, fatigue, and resilience to disturbing sensory stimuli.

[0020] The IMU module is configured to assess postural imbalances by capturing three-dimensional data on the user's body orientation and acceleration, thus providing an analysis of postural stability.

[0021] The capacitive touchscreen allows for the presentation of sequential cognitive tests, including cognitive flexibility tests, sensory interference tests, and tests of tolerance to dynamic visual stimuli.

[0022] The wireless connectivity module includes Bluetooth and Wi-Fi connectivity, enabling secure data transmission to an external storage device or remote analysis application.

[0023] The device is configured to display real-time performance indicators on the touchscreen, including values ​​such as heart rate, postural stability, and cognitive test results.

[0024] The device includes an energy-saving mode that automatically reduces the device's energy consumption when the sensors are not actively used.

[0025] Data analysis is performed locally on the integrated processor, allowing for immediate evaluation of the user's neurocognitive and physiological responses to stimuli

[0026] The device is configured to perform self-calibration of the sensors to ensure the accuracy of movement and heart rate data in various environments and conditions of use.

[0027] Description of a non-exhaustive example of implementation

[0028] The present invention will be better understood upon reading the following description concerning a non-limiting embodiment, illustrated by the accompanying drawings where:

[0029] The figure represents a schematic diagram of the device according to the invention. General principle of the invention

[0030] The invention relates on the one hand to an autonomous and portable device with interfaces for capturing biological signals from the user and human-machine interactions, and on the other hand to a battery of tests recorded in the device's memory and executed by the device.

[0031] The device consists of a housing (10) with a touchscreen (11), for example a capacitive touchscreen for user interaction during standardized cognitive tests, and an electronic circuit (12). This electronic circuit (12) includes a processor (13) executing configured processes for real-time data acquisition and analysis, and a memory (14) for storing captured data and computer programs.

[0032] The device further includes an ECG module (15) for capturing the user's heart rate variability (HRV) in response to sensory and cognitive stimuli, an inertial measurement unit (IMU) module (16) comprising an accelerometer and a gyroscope, configured to detect and record the user's movements and posture, and a wireless connectivity module (17) for transmitting data to an external device. The housing also includes LEDs (18, 19).

[0033] The device is designed to acquire, process and exploit in real time physiological and cognitive data of the user, in order to detect characteristic responses to disturbing sensory stimuli, including multisensory conflicts between visual, vestibular and proprioceptive perceptions, such as those encountered in situations of movement (motion sickness) or virtual immersion (cybermotion sickness), including when the user is in an uncontrolled environment.

[0034] Characteristic responses to disturbing sensory stimuli are the measurable physiological and cognitive reactions of the user (such as heart rate variations, postural imbalances, or changes in cognitive performance), in response to certain stimuli identified as sensorially disturbing.

[0035] Characteristic responses are objectively observable manifestations of a sensory or cognitive disorder. For example: A decrease in heart rate variability (HRV) under the effect of sensory stress (perceived via the ECG module), An increase in postural sway or unbalanced movements (detected by the IMU module), A decrease in performance during interactive cognitive tests (measured via the screen interface), A prolonged reaction latency, a memory or coordination error.

[0036] These responses are characteristic because they are associated, in the literature as well as in clinical practice, with states of sensory disorientation, cognitive fatigue, or physiological discomfort.

[0037] Disruptive sensory stimuli are conflicting multisensory inputs that lead to misalignment between sensory systems (vision, proprioception, vestibular). These stimuli typically include: unanticipated or contradictory vehicle movements (e.g., reading in a moving car); dynamic virtual scenes (in a VR headset) where vision suggests movement not corroborated by the inner ear (cybermotion); and immersive visual stimulation with low vestibular feedback (simulation platforms, panoramic displays).

[0038] Sensory conflicts induced by artificial environments, such as those encountered in simulators or immersive experiences.

[0039] These stimuli can be exogenous (visual, auditory, dynamic environment) or endogenous (prolonged static postures, intense cognitive focus in a disturbed context).

[0040] Disruptive sensory stimuli include situations of conflict between vestibular, visual and proprioceptive signals, such as those encountered during vehicle travel, use of virtual reality headsets, or exposure to visually immersive environments.

[0041] Description of ECG (Electrocardiogram) signal sensors

[0042] The device includes a connector for ECG (Electrocardiogram) signal sensors that measure the heart's electrical signals generated during each heartbeat. These signals are represented by a PQRST wave, which corresponds to the activity of the different phases of the cardiac cycle. The ECG sensor allows for real-time measurement of these signals, providing precise resolution for assessing cardiac function in dynamic or resting situations. The ECG is used to observe heart rate and rhythm regularity, critical elements in contexts of stress, fatigue, or neurocognitive disorders.

[0043] The ECG sensor (20) works by placing two or more skin electrodes (21, 22) on the user's body, which capture the electrical potentials generated by the myocardial cells. These signals are then amplified, filtered, and analyzed by the device's processor to determine characteristics such as heart rate and specific intervals (PR, QT).

[0044] Heart rate variability (HRV) represents the fluctuation over time between two consecutive heartbeats, a key indicator of the autonomic nervous system. The ECG sensor allows for the measurement of this variability with high precision. HRV analysis makes it possible to distinguish the activity of the two branches of the autonomic nervous system: the sympathetic nervous system (related to stress and activity) and the parasympathetic nervous system (related to relaxation and rest).

[0045] A high heart rate variability (HRV) generally indicates a good balance between the sympathetic and parasympathetic nervous systems, reflecting an increased ability to adapt to stressful situations. Conversely, a low HRV can be an indicator of fatigue, chronic stress, or other pathological conditions. The device according to the invention captures these fluctuations during postural and cognitive tests, or during rest and exertion phases (such as 3 minutes lying down followed by 3 minutes standing), thus allowing for the assessment of postural-cardio coherence and physiological responses to fatigue, alertness, and stress.

[0046] The ECG system uses reusable adhesive electrodes, specially designed for application to the skin without causing irritation. These electrodes are strategically positioned on the user's torso to capture cardiac electrical signals with high precision.

[0047] The electrodes (21, 22) are wired with low-impedance connectors to ensure good signal conductivity. The electrode materials (21, 22) are hypoallergenic and can be repositioned according to the user's anatomy.

[0048] The reference electrode is placed on the sternum, while the active electrodes are positioned on areas of the torso to maximize the capture of PQRST waves. This arrangement ensures optimal signal capture even during slight movements, thus reducing the risk of interference.

[0049] The ECG sensor (20) has a sensitivity of approximately 0.5 millivolts (mV), enabling precise detection of variations in the heart's electrical potential. This precision is essential for identifying cardiac irregularities such as arrhythmias and for performing accurate heart rate variability (HRV) analyses.

[0050] The signals captured by the ECG are processed in real time via sophisticated algorithms to ensure optimal data quality.

[0051] The invention uses advanced digital filters to suppress background noise and motion artifacts often caused by user movement.

[0052] Low-pass filtering eliminates unnecessary high frequencies that could interfere with ECG data, while adaptive filtering algorithms automatically adjust sensitivity based on user activity (movement, rest, etc.).

[0053] Once the ECG signals are filtered, the heart rate variability (HRV) calculation algorithm analyzes the RR intervals (time between two heartbeats).

[0054] Two main approaches are used for HRV analysis: Time-domain analysis: This method directly measures fluctuations in RR intervals to determine heart rate drift over time. Frequency-domain analysis: This method uses the Fourier transform to separate ECG signals into different frequency bands, allowing for the differentiation of variations due to components of the sympathetic and parasympathetic nervous systems. HRV Analysis

[0055] Heart rate variability (HRV) analysis allows for the assessment of the body's autonomic responses. The HRV system uses specific frequency bands to differentiate between responses of the sympathetic nervous system (related to the stress response) and the parasympathetic nervous system (related to relaxation).

[0056] The frequency bands used are as follows: LF (Low Frequency, 0.04 to 0.15 Hz): Variations in this band are primarily influenced by the sympathetic nervous system and are often associated with states of stress or physical exertion. HF (High Frequency, 0.15 to 0.4 Hz): This band is primarily modulated by the parasympathetic nervous system, particularly during respiration and resting states. Strong activity in this band generally indicates good heart regulation and an ability to relax.

[0057] The ratio between LF and HF bands is used to assess autonomic balance. A high ratio may indicate a predominance of stress or excessive activation of the sympathetic nervous system, while a low ratio is often synonymous with relaxation or recovery.

[0058] Description of the IMU (Gyroscope and Accelerometer) module and postural measurements

[0059] The IMU module (16) is a component designed to measure body movements and postural balance in real time. This module (16) combines two main sensors:

[0060] The IMU module (16) combines a 3-axis gyroscope and accelerometer, which respectively measure the angular rotations and linear accelerations of the body in three dimensions (x, y, z). These sensors are designed to capture body movements, including postural micromovements, enabling a precise assessment of postural stability and dynamic balance.

[0061] The first sensor is a gyroscope: it measures angular rotations around the three axes (x, y, z) to detect changes in body orientation. It allows for the tracking of rotational movements such as tilts or twists, often affected during episodes of motion sickness or sensory imbalances. The gyroscope in the IMU module (16) measures rotations with a sensitivity of ±250 degrees / second to ±2000 degrees / second, depending on the configured scale. It enables the tracking of rotational body movements with high precision, capturing changes in orientation during situations of imbalance or sudden movement.

[0062] The second sensor is an accelerometer: It measures the linear accelerations experienced by the body in three directions (front-back, lateral, vertical). This sensor is crucial for detecting displacements and changes in speed, particularly in postural tests and body stability assessments. The integrated accelerometer measures linear accelerations with a sensitivity of ±2g to ±16g and a resolution of 0.001 m / s², enabling the detection of subtle changes in position and linear body movements in postural contexts. This precision allows for the identification of minimal oscillations in anteroposterior and lateral movements, often associated with balance or coordination disorders.

[0063] The IMU (16) module has a 16-bit resolution for the gyroscope and accelerometer, ensuring accurate measurement of body movements, and a configurable sampling frequency of up to 1000 Hz, enabling the capture of postural micromovements in real time, even in disturbed environments.

[0064] The IMU sensor (16) enables continuous monitoring of body position and postural adjustments by providing accurate data on movements in a three-dimensional space.

[0065] The module is used to assess postural imbalances in various tasks, such as: Single postural task: The device measures body stability by capturing center of pressure (COP) oscillations in the anteroposterior and lateral planes. This measurement is used to assess the patient's static balance ability. Dual postural and cognitive task: The IMU module is also used in combined tasks, where the subject must maintain a posture while performing a cognitive test, such as mental arithmetic or an auditory task. This type of assessment allows for the analysis of the impact of cognitive impairments on body stability, a key factor in the diagnosis of motion sickness, postural fatigue, or sensory overload.

[0066] The data collected by the IMU module are processed in real time, allowing for the evaluation of: Postural shifts under cognitive stress (posturo-cardio test). The coherence between the vestibular system and posture, particularly during tests where visual, vestibular, and proprioceptive coordination is required. Autonomic body reactions, often affected during episodes of motion sickness or spatial disorientation, for example, during movement or prolonged exposure to immersive environments. Calibration and error correction

[0067] Calibrating the IMU module (16) ensures accurate measurements and avoids drift in data, particularly during rapid movements or in contexts where cumulative errors may occur, such as in prolonged testing or dynamic environments (motion sickness, cybersickness).

[0068] The IMU module (16) is equipped with an automatic calibration system that regularly adjusts measurements according to environmental conditions. This allows the sensors to be reset to stable reference points to compensate for any drift that could affect long-term data accuracy.

[0069] To compensate for errors due to sudden or irregular movements, the module uses adaptive filtering and sensor fusion algorithms. These algorithms combine gyroscope and accelerometer data to correct angular and linear deviations that can occur during complex movements, such as those observed in motion sickness or cybersickness. The correction algorithms include the use of Kalman filters to reduce noise in the data and improve the accuracy of postural measurements.

[0070] The IMU module (16) also incorporates gravity compensation algorithms, allowing the subject's actual movements to be isolated from accelerations caused by Earth's gravity. This is particularly important for posture and balance tests, where accurate measurement of body displacements is crucial for assessing the subject's neurocognitive and physiological responses. Applications of ECG and HRV:

[0071] The device uses these measurements in several contexts. For each type of test, HRV plays a key role as a measure of the body's physiological response to disturbing sensory stimuli:

[0072] HRV is used to detect heightened sensitivity to motion sickness in response to sensory stressors. A decrease in HRV may indicate greater vulnerability to disturbances, as it reflects the autonomic nervous system's difficulty in adapting to sensory conflicts.

[0073] In anticipation tests, a decrease in HRV before exposure to stimuli indicates anticipatory stress. This shows that the subject is already experiencing physiological tension in anticipation of a sensoryally uncomfortable situation, which can predict the severity of future symptoms.

[0074] HRV quantifies mental and physical fatigue. A decrease in HRV indicates reduced adaptive capacity, which can exacerbate susceptibility to motion sickness and cybersickness. Measuring HRV before and after fatigue tests is essential for assessing physiological resilience.

[0075] HRV is used for motion sickness depth testing to assess the severity of symptoms once induced. A marked reduction in HRV during exposure to disturbing stimuli indicates a strong physiological response, confirming the depth of the sensory effects.

[0076] Thus, ECG and HRV analysis make it possible to capture essential information about the user's physiological state, offering a holistic view of the impact of sensory disturbances and stressful situations on cardiac health and general well-being.

[0077] Detailed description of the device components

[0078] The device includes a modular architecture and components specifically adapted to environments requiring real-time measurements and multiple interactions.

[0079] The processor (13), for example, is an ESP32 (trade name). This dual-core processor is based on an Xtensa LX6 (trade name) architecture operating at a frequency of 240 MHz, capable of handling multiple tasks simultaneously, such as sensor data acquisition, real-time information processing, and cognitive testing. This processor (13) also integrates Wi-Fi and Bluetooth connectivity, enabling fast and reliable data transmission.

[0080] The electronic circuit (10) is equipped with 16 MB of flash memory (14) and 520 KB of RAM, allowing for the temporary storage of test results and captured data before their transfer to external devices. The flash memory (14) also allows for the storage of firmware and software updates, ensuring flexibility of use and the ability to upgrade the device.

[0081] The device is equipped with Bluetooth Low Energy (BLE) technology, which enables data transmission with minimal power consumption. This feature is essential for maintaining a smooth connection with external devices, such as smartphones or computers, for extended periods without compromising battery life.

[0082] In addition to the processor and memory, the device is equipped with several integrated sensors via its add-on modules, such as the ECG sensor (15) and the IMU module (16). These sensors interact directly with the processor to record physiological data in real time. The IMU module (16) provides rotational and linear acceleration measurements, which are particularly important in the assessment of postural disorders or motion sickness.

[0083] The device features an 11-inch capacitive touchscreen, providing an intuitive user interface for easy navigation between cognitive tests and real-time results. This screen also allows users to interact directly with the device's functions, making the entire system self-contained and easy to use without additional assistance. Physical design

[0084] The device's shape is optimized for portability and durability. The compact case (10) is made of impact-resistant materials, with rounded edges for optimal user comfort. The device is designed for easy transport, ensuring an ergonomic grip for users, even during testing on the move or in dynamic environments.

[0085] The casing is designed to offer both robustness and ergonomics, ensuring high durability and comfortable use in a variety of environments. The casing is made of ABS (Acrylonitrile Butadiene Styrene) plastic, chosen for its impact resistance and lightweight properties. This plastic is commonly used in industry for its robustness against impacts and vibrations, which is essential for a portable device subjected to frequent movement. Furthermore, this material is antistatic, minimizing the accumulation of dust and other particles, thus ensuring the proper functioning of the internal electronic components.

[0086] ABS plastic, combined with an antistatic treatment, gives the casing excellent protection against mechanical damage while reducing the accumulation of electrostatic charges, an essential aspect in clinical or research environments where electrical interference can affect results.

[0087] To further enhance durability, our device is designed to IP54 standards, guaranteeing moderate resistance to water and dust (dustproof). The IP54 rating protects the device against splashing water and limited dust penetration, ensuring reliable performance in outdoor environments or under varying conditions.

[0088] The electronic circuit (12) is powered by a high-capacity lithium polymer battery (1), providing extended battery life to allow for prolonged sessions without recharging. The battery has a capacity of 3000 mAh, ensuring up to 24 hours of continuous use depending on the intensity of the tests and the sensors activated.

[0089] The device incorporates intelligent power management mechanisms to maximize battery life. This includes a power-saving mode that reduces battery consumption when sensors are not actively used, as well as an automatic sleep mode when the device is inactive for a certain period. This mode temporarily pauses sensors such as the ECG and IMU, extending battery life without compromising performance during active testing.

[0090] Thanks to a USB-C port, the battery (1) can be quickly recharged, allowing the device to reach a full charge in less than two hours. This ensures that the device is always available for evaluation sessions without having to endure long periods of downtime.

[0091] The connectivity module (17) features advanced wireless connectivity capabilities via Bluetooth 5.0 (BLE) and Wi-Fi, with a transmission range of up to 50 meters for Bluetooth in open environments. The Bluetooth 5.0 standard ensures low power consumption while maintaining optimal data transfer speeds, which is particularly useful for continuous interaction with external devices such as smartphones or computers.

[0092] All data transmitted via Bluetooth and Wi-Fi is protected by AES-128 encryption protocols to ensure the confidentiality and security of sensitive information, particularly when transmitting physiological or cognitive data to external databases. Software and User Interface

[0093] The device is equipped with a high-resolution capacitive touchscreen (11"), facilitating user interaction through an intuitive interface. The user interface allows for seamless navigation between the various cognitive and physiological tests. The tests are presented sequentially, with clear instructions to guide the user through each step of the assessment.

[0094] At the end of each test, real-time results are displayed on the screen, including metrics such as reaction times, heart rate, and performance indices. These results can be immediately viewed by the user or transmitted to a third-party device for further analysis.

[0095] The software is scalable, with over-the-air (OTA) updates available via Wi-Fi, ensuring that our device's functionality is regularly enhanced without requiring physical intervention. Available APIs also allow for easy integration with external platforms, such as medical data management software or advanced analytics tools. Displaying results

[0096] Motion sickness sensitivity is displayed as a color-coded thermometer graphic.

[0097] A vertical thermometer with color-coded levels ranging from green at the bottom to red at the top. The higher the level, the greater the sensitivity to motion sickness. The thermometer's intuitive design indicates a scale of increasing sensitivity. A "wave" or "movement" icon at the top of the thermometer represents motion sickness, and numerical markings or visual increments allow for accurate readings.

[0098] The level of anticipatory stress is displayed as a graphic representing a circular barometer with a needle pointing towards a stress level, from "Low" (green) to "High" (red). A circular gauge reflects levels of anticipatory tension, with the needle moving according to the result.

[0099] Motion Sickness Depth: Gradient bar with a shaking effect. A horizontal progress bar that changes color with a gradient from light blue (low depth) to dark red (high depth). The bar may include a slight shaking or vibration effect that intensifies with the depth of motion sickness. The greater the depth of motion sickness, the more the bar's color shifts toward red, and the more visible the shaking effect becomes. The shaking effect is visually engaging without being overly complex to display, and the color gradient allows for a quick assessment of symptom severity.

[0100] Application of the device for conducting tests

[0101] The device described above uses a series of standardized tests to assess individual susceptibility to these disorders, the reaction to anticipatory stress, and the severity of symptoms once induced. It allows for the capture of neurocognitive and physiological responses without requiring external sensors or video recording systems. Motion Sickness Assessment

[0102] Motion sickness is one of the most common disorders experienced during movement or interaction with visually immersive environments (e.g., virtual reality). It manifests as a sensory conflict between visual, vestibular, and proprioceptive signals. The invention enables the measurement, analysis, and comparison of users' reactions in real time, directly within these environments.

[0103] Traditional methods for assessing motion sickness, such as the MSSQ (Motion Kinetic Susceptibility Questionnaire) or VIMSSQ (Visually Induced Motion Kinetic Susceptibility Questionnaire), provide useful information but do not capture immediate physiological or cognitive responses to stimuli. These questionnaires are used for an initial assessment of individual susceptibility before progressing to more dynamic testing. Vestibular tests

[0104] Vestibular testing assesses the function of the vestibular system, located in the inner ear, which plays a key role in the perception of balance and spatial orientation. Vestibular system disorders are often associated with sensations of dizziness, disorientation, and nausea—common symptoms of motion sickness and cybersickness. By incorporating vestibular testing, the device aims to analyze postural stability in response to external stimuli, evaluate the vestibular system's responsiveness and sensitivity to movement, which can reveal heightened susceptibilities to disturbing environments, and identify sensory disturbances related to a desynchronization between vestibular and visual signals, a common phenomenon in virtual reality and motion environments.

[0105] Cognitive flexibility and management of cognitive interference

[0106] Cognitive flexibility refers to the brain's ability to adapt to new information or changing tasks, while managing cognitive interference involves the ability to ignore distractions or irrelevant information to focus on a specific task.

[0107] In the context of motion sickness and cybersickness: A deficit in cognitive flexibility can make an individual more susceptible to sensory conflicts, for example, when switching from a visual to a motor task or when exposed to changing environments. Managing cognitive interference is crucial for maintaining stable attention despite conflicting stimuli, such as those encountered in virtual environments or during a bumpy journey. Individuals who have difficulty managing this interference may be more prone to sensory disturbances. Aggravating factors

[0108] Vestibular disorders and cognitive abilities play a major role in the severity of motion sickness and cybersickness symptoms. For example, reduced cognitive flexibility or poor interference management can lead to greater disorientation, as the brain struggles to adapt to conflicts between different sensory signals (such as vision and vestibular signals). Integrating vestibular and cognitive testing would therefore allow for a better understanding of these individual susceptibilities and for tailoring interventions to reduce symptoms.

[0109] Physical and mental fatigue are equally considered an aggravating factor.

[0110] In summary, assessing these factors provides a holistic view of the individual facing sensorimotor disturbances, allowing for a more targeted approach to managing and mitigating sensory disorders. Test descriptions

[0111] Visual stabilization test: The objective of this test is to simulate a vestibular assessment based on visual stabilization. A series of bright dots appear successively on the screen, and the subject must maintain their gaze fixed on each dot for a defined interval, rapidly changing from one dot to another.

[0112] The aim is to test the brain's ability to stabilize the image in the event of body movements, which is crucial for detecting sensory imbalances.

[0113] The user must tap the touchscreen when each dot appears. The device records the response and timing of the tap, allowing for an assessment of the user's ability to maintain visual stability. Performance indicators are determined by the response time and accuracy in tracking the dots.

[0114] Sequenced Cognitive Flexibility Test: This test measures the ability to manage transitions between tasks using only the elements displayed on the touchscreen. The user is presented with sequences of different tasks, such as identifying geometric shapes followed by simple calculations. Its purpose is to assess cognitive flexibility, an important ability for managing changing environments, such as virtual reality. The device displays changing sequences of instructions (for example, selecting colors, then performing calculations), and the subject must quickly follow these instructions using the touchscreen.

[0115] The performance indicator consists of transition time between tasks and error rate.

[0116] Conflicting Stimulus Response Test: This test is designed to assess cognitive interference management. The screen displays conflicting stimuli (e.g., color words and mismatched ink colors), and the user must choose the correct ink color while ignoring the word. The goal is to measure the ability to manage sensory conflicts, which are often present in cybermotion.

[0117] The device displays a series of colored words, and the subject must tap the corresponding ink color on the touchscreen, without knowing the word's meaning. The device records response times and errors. Performance indicators are response speed and accuracy.

[0118] Cognitive Balance Test (Simple Dual Task): This test simulates a dual task to assess the ability to maintain cognitive balance in disruptive situations. The user must solve simple mathematical calculations while performing specific gestures on the touchscreen, such as drawing lines or following patterns.

[0119] Its aim is to test the brain's ability to handle complex cognitive tasks under sensory stress. Visual instructions appear on the screen asking the subject to perform specific motor tasks (such as tracing a line with their finger) while mentally solving mathematical problems and entering the answers on the screen.

[0120] The performance indicators are the measurement of coordination and response time for the two tasks.

[0121] Progressive Sensory Conflict Test: This test simulates a conflict between visual stimuli and instructions to assess the ability to manage sensory disturbances. Its purpose is to measure the reaction to increasing sensory conflicts, which are classic triggers of motion sickness and cybersickness. The device displays visual sequences of movement (such as lines that oscillate or change direction) while auditory or visual instructions require the user to act differently (e.g., touch the screen when the direction is straight even if the line is moving in a curve). Performance indicators are Response Time and errors in choice, indicating difficulty in managing conflicting signals.

[0122] Virtual Motion Detection Test: The screen displays animations simulating movement (such as slow rotation or forward and backward movement) to assess visual motion sensitivity. Its purpose is to analyze the brain's ability to interpret virtual movements and their impact on sensory balance. The user must accurately indicate when they perceive specific movements or changes in the direction of the animations. The device records the responses and adjustments on the screen. The performance indicators are the accuracy and time it takes to detect movements or changes in direction, revealing susceptibility to cyber motion sickness.

[0123] Visual Rotation Tolerance Test: The device displays an object that rotates slowly and gradually accelerates, while requiring the user to track the object with their eyes or interact with the screen in response to the rotations. Its purpose is to measure tolerance to rotating visual stimuli, which are often problematic in cases of motion sickness and cybersickness. The user must touch the screen when a rotating object reaches a specific position or changes color. The gradual acceleration allows for the measurement of tolerance to circular movements. Performance indicators include the ability to track rotating objects without errors and without significant slowing of response.

[0124] Real-time Sensory Adaptation Test: This test requires the user to gradually adapt to changing sensory stimuli by interacting with the screen in response to subtle modifications (such as slightly changing colors or slowly moving elements). Its purpose is to assess sensory adaptation and tolerance to dynamic visual environments. The device introduces changing visual stimuli, such as color gradients or slow-moving elements, and requires the user to touch or interact with specific elements only when a change is perceived. This test tests the ability to identify subtle changes while ignoring other distractions. Performance indicators include accuracy and the time required to adapt to the changes, assessing tolerance and sensory adaptation—key factors in situations of cyber motion sickness.

[0125] Anticipatory Stress Assessment. This motion anticipation test with visual preview introduces anticipated visual stimuli that simulate potentially uncomfortable movements. Its purpose is to assess anticipatory stress in response to visual stimuli perceived as disturbing. The device displays a series of animations simulating movements, with a preview before each simulation (e.g., a "pre-movement" sequence indicating a turn or rapid movement). The user indicates their level of anticipated comfort or discomfort on the screen by touching a stress scale before the movement actually begins. Performance indicators measure the anticipatory responses, including indications of discomfort even before the movement is simulated. Stress levels are assessed based on the frequency and intensity of the responses.

[0126] Progressive Tolerance Stimulus Test with Announcement: This test uses increasing visual stimuli but announces each step of intensification in advance to observe the anticipatory response. Its purpose is to identify sensitivity to anticipatory disturbances in visual motion. The device progressively announces increasingly intense movements (such as an increase in the rotational speed of an object on the screen) and asks the user to prepare for each step by touching a "ready" button. The intensity gradually increases, and the subject must report any anticipatory discomfort. Performance indicators include the frequency and intensity of the anticipatory cues, as well as the subject's willingness to continue the announced steps.

[0127] Anticipatory Stress Decision Test: This test focuses on decision-making under anticipatory stress with instructions that change unexpectedly. Its purpose is to analyze decision-making and the speed of choice in the face of a stressful and anticipated environment. The device displays a series of choices to be made on the screen (e.g., choosing a visual navigation route on a screen) within a time limit. The user receives an alert before each decision, simulating a stressful context where an uncomfortable action might occur. The performance indicators are response time and accuracy in decision-making, revealing signs of anticipatory stress.

[0128] Sensory Conflict Anticipation Test: This test assesses the anticipatory response to a sensory conflict by creating a situation of anticipated discomfort where conflicting visual stimuli are announced. Its purpose is to measure the stress experienced before a potential sensory conflict. The device announces in advance that a conflicting sequence will occur, for example, contradictory movements (a screen rotation combined with moving images). The user must indicate their stress level on an intensity scale before the sensory conflict occurs. The performance indicators are the level of anticipated stress, measured before actual exposure to the sensory conflict, and the differences between the anticipated stress and the stress actually experienced during exposure.

[0129] These tests are designed to capture an individual's emotional and cognitive response when anticipating disturbing stimuli, using only the device's interface and capabilities, without requiring external equipment.

[0130] Motion Sickness Assessment: This subjective symptom severity rating test aims to quantify the severity of motion sickness experienced by the individual using a standardized subjective scale. Its purpose is to assess the personal perception of motion sickness. The device presents a series of questions via a touchscreen to evaluate the intensity of symptoms such as nausea, dizziness, sweating, and headache. The user responds on a scale of 1 to 10 (or from "mild" to "severe"). The performance indicator is the total score, which allows motion sickness to be classified into different severity categories (mild, moderate, severe).

[0131] The Pointing Accuracy Test (motor coordination) aims to assess the effect of motion sickness on fine motor skills and eye-hand coordination, and to analyze the impact of motion sickness on motor precision. The device displays increasingly smaller targets on the screen that the subject must touch accurately. The difficulty gradually increases to measure the loss of coordination due to motion sickness symptoms. Performance indicators are response time and the accuracy of actions on the screen, indicating the severity of motor disorientation.

[0132] Postural Stabilization Test (Sway Test): This test assesses a subject's ability to maintain a stable position despite the presence of motion sickness symptoms. Its purpose is to quantify the effects of motion sickness on postural stability. The device requires the subject to remain still while following a cognitive task displayed on the screen. Body deviations or the inability to maintain position are assessed by detecting movements on the touchscreen. Performance indicators include the measurement of the amplitude and frequency of body movements, indicating difficulties with postural control.

[0133] Prolonged Visual Motion Tolerance Test. This test measures a subject's ability to tolerate a visual stimulus that simulates continuous motion, a typical trigger of motion sickness. Its purpose is to determine the tolerable duration and intensity of disturbing visual motion. The device displays continuous visual motion (such as a scene of movement in a virtual environment) and asks the subject to indicate when they begin to experience symptoms or when they can no longer tolerate the stimulus. Performance indicators are the time to report the first symptoms and the intensity of subjective responses, providing an indication of the severity of motion sickness.

[0134] Sensory Stress Cognitive Impairment Test: This test assesses cognitive performance in the presence of motion sickness symptoms to measure the impact on concentration and executive functions. Its purpose is to analyze the effect of motion sickness on cognitive abilities, such as attention and memory. The device presents cognitive tests (such as simple calculations and visual memory tasks) while displaying a disturbing visual stimulus. The results are compared to baseline performance obtained in the absence of motion sickness. Performance indicators include the error rate, response time, and accuracy of cognitive responses under sensory stress, indicating a decrease in cognitive ability related to motion sickness.

[0135] These tests make it possible to measure not only the depth of motion sickness symptoms, but also their effects on coordination, stability, and cognitive functions, thus providing a comprehensive assessment of the severity of sensory and cognitive impairments.

[0136] Fatigue assessment: Fatigue is a major aggravating factor in the onset and severity of motion sickness. When an individual is fatigued, the brain's ability to properly process and integrate sensory information is reduced. This can increase sensory desynchronization, that is, the difference between what the eyes see, what the vestibular system feels, and what the body perceives in terms of movement. This desynchronization is the primary cause of motion sickness symptoms.

[0137] Flicker Test: The flicker test in our device relies on the use of high-precision light-emitting diodes (18, 19) to generate a variable-frequency flashing light. This test is designed to evaluate visual flicker fusion, a phenomenon where a high-frequency flashing light stimulus becomes perceived as continuous by the human eye.

[0138] The system uses LEDs (18, 19) capable of blinking at frequencies between 10 Hz and 100 Hz. The minimum frequency of 10 Hz corresponds to blinks visible under most normal conditions, while the maximum frequency of 100 Hz tests the limits of visual perception and measures eye strain due to motion sickness or cybersickness. The subject observes the blinking and must indicate when they no longer perceive any flicker, thus reaching the critical fusion frequency. This measurement is directly related to the state of visual alertness and oculomotor fatigue, which is often affected by sensory desynchronization in conflicting environments (e.g., during motion sickness or exposure to immersive visual stimuli such as virtual reality).

[0139] The test results are accurately recorded via integrated sensors that capture the subject's response to each frequency. The data is then compared to normative values ​​to identify perceptual or fatigue deficits.

[0140] Psychomotor Vigilance Test (PVT): This test measures a subject's reaction times to visual stimuli presented at random intervals. It is widely used to assess vigilance and cognitive responsiveness, particularly in situations of fatigue. The subject interacts with the touchscreen of our device each time a visual stimulus appears. The latencies between stimulus appearance and the subject's response are measured with millisecond precision. This data is analyzed to identify long reaction times, which are indicators of cognitive fatigue or attentional deficits. Errors (e.g., responses that are too fast or too slow) and delayed responses are interpreted to provide an accurate diagnosis of vigilance and fatigue levels. These results can be cross-referenced with HRV or ECG data to assess the impact of stress on cognitive performance.

[0141] The CPT is a sustained vigilance test used to measure an individual's ability to maintain prolonged attention on a repetitive task. The CPT presents the subject with a series of visual stimuli on the screen of our device, and they must identify a specific target. Each interaction is recorded in real time, measuring the speed of responses as well as inattentional errors (e.g., missing a target). Response times and inattentional errors are analyzed to provide clues about attentional deficits, a key indicator of sensory disorders such as cyber motion sickness. Incorrect responses are correlated with physiological data to establish links with stress or cognitive disorientation.

[0142] The Stroop Test is designed to assess executive functions and the brain's ability to resolve cognitive conflicts. The subject must respond to stimuli where the meaning of the words and the ink color are contradictory. For example, the word "red" might be written in blue. The test measures the user's ability to inhibit the automatic response to provide the correct answer. The test records response times and errors (for example, when the subject responds to the word rather than the color). These results are interpreted to assess deficits in cognitive inhibition, which are often exacerbated by stress or sensory disorientation.

[0143] Advanced cognitive tests: PSVAT and mental calculation: These tests assess calculation and sustained attention skills, essential for measuring the effects of stress or cognitive fatigue in dynamic environments.

[0144] PSVAT (Paced Serial Visual Addition Test): The subject sees a series of numbers appear on the screen and must perform simple or complex additions within a time limit. The device automatically calculates the correct answers and response speed, taking into account variables such as fatigue or stress, identified through physiological measurements like ECG or HRV.

[0145] Mental arithmetic: This test requires the subject to solve mathematical problems within a given time while being exposed to distracting visual stimuli or postural tasks. Errors and response times are recorded and analyzed to provide an accurate assessment of working memory under stress. Voice capture and stress analysis

[0146] The device is equipped with a voice capture module that records the subject's voice during interactions with the device. Voice analysis allows for the measurement of stress levels through changes in tone, cadence, and vocal modulations.

[0147] Advanced algorithms analyze vocal variations, providing insights into levels of emotional stress and psychological tension during or after cognitive tests. This data is particularly useful for individuals suffering from motion sickness or cybersickness, where stress can exacerbate symptoms.

Claims

A portable and self-contained device for the assessment of sensory and cognitive disorders, characterized in that it comprises: a processing unit configured for real-time data acquisition and analysis; an ECG module for capturing the user's heart rate variability (HRV) in response to sensory and cognitive stimuli; an inertial measurement unit (IMU) comprising an accelerometer and a gyroscope, configured to detect and record the user's movements and posture; a capacitive touchscreen for user interaction for the performance of standardized cognitive tests; integrated memory for storing captured data and programs; a wireless connectivity module for transmitting data to an external device;and in that the device includes technical means for acquiring and processing in real time the user's physiological and cognitive data in order to characterize responses to disturbing sensory stimuli, including those likely to cause motion sickness or cybersickness, when the user is in an uncontrolled environment. Device according to claim 1, characterized in that the ECG module is configured to measure the heart rate variability (HRV) of the user, and in which the processor is arranged to analyze, in real time, said variability as a function of sensory or cognitive stimuli detected during interaction with the device. Device according to any one of the preceding claims, characterized in that the IMU module is configured to assess postural imbalances by capturing three-dimensional data of the orientation and acceleration of the user's body, thus providing an analysis of postural stability. Device according to any one of the preceding claims, characterized in that the capacitive touchscreen allows for the presentation of sequential cognitive tests, including cognitive flexibility tests, sensory interference tests, and tests of tolerance to dynamic visual stimuli. Device according to any one of the preceding claims, characterized in that the wireless connectivity module includes Bluetooth and Wi-Fi connectivity, enabling secure transmission of data to an external storage device or remote analysis application. Device according to any one of the preceding claims, characterized in that the device is configured to display real-time performance indicators on the touch screen, including values ​​such as heart rate, postural stability, and cognitive test results. Device according to any one of the preceding claims, characterized in that the device includes an energy saving mode which automatically reduces the energy consumption of the device when the sensors are not actively used. Device according to any one of the preceding claims, characterized in that the data analysis is performed locally on the integrated processor, allowing an immediate evaluation of the user's neurocognitive and physiological responses to stimuli. Device according to any one of the preceding claims, characterized in that it is configured to perform self-calibration of the sensors to ensure the accuracy of movement and heart rate data in various environments and conditions of use.

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