Method, device and system for evaluating cognitive ability based on visual stimulation modulation

Abstract

The invention relates to the technical field of visual cognitive ability evaluation, and discloses a method for evaluating cognitive ability based on visual stimulation modulation, which comprises the following steps: collecting visual stimulation modulation electroencephalogram response induced by a to-be-tested object based on a contrast target and a cognitive target; wherein the visual stimulation modulated electroencephalogram response represents the response frequency generated by the steady-state visual evoked potential of the to-be-tested object; determining reference spectrum energy corresponding to the contrast target in the visual stimulation modulated electroencephalogram response and cognitive spectrum energy corresponding to the cognitive target in the visual stimulation modulated electroencephalogram response; and evaluating the cognitive ability of the to-be-tested object by using the reference spectrum energy and the cognitive spectrum energy. According to the method, the contrast target and the cognitive target are used as specific cognitive tasks, and a clearer feature mark can be induced in the brain signal of the to-be-tested object, so that the influence of subjective factors and external interference factors of the to-be-tested object on an evaluation result is reduced, and the accuracy of cognitive ability evaluation by a brain-computer interface is improved.

Description

Technical Field

[0001] The present application relates to the technical field of visual cognitive ability assessment, for example, to a method, device and system for assessing cognitive ability based on visual stimulation modulation. Background Art

[0002] Traditional cognitive ability assessment methods rely on questionnaires, scale assessments, and expert experience judgment. The assessment results are easily affected by multiple subjective factors such as personal bias, social desirability bias, subjectivity of the assessor, and limitations of the situational factor scale itself. In order to reduce the impact of subjective factors, researchers and clinicians need to adopt a variety of assessment tools and methods and combine multiple information sources to obtain a more comprehensive and objective cognitive ability assessment. Therefore, researchers have tried to assess cognitive function by measuring brain activity through brain-computer interface technology.

[0003] In order to evaluate cognitive ability through brain-computer interface technology, the relevant technology discloses a method for evaluating visual cognitive ability based on EEG signals, including: collecting EEG signals of subjects performing visual cognitive task paradigm experiments under a specified working memory paradigm; preprocessing the EEG signals to extract the average standard time-frequency diagram of the subjects' working memory; for the average standard time-frequency diagram of the working memory, using a moving window to extract the window energy of the beta frequency band and averaging the desynchronization energy value DEV as the evaluation result of the subjects' visual cognitive ability.

[0004] In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art:

[0005] The relevant technology requires users to conduct visual cognitive task paradigm experiments under the working memory paradigm, which is only effective for the "specified working memory paradigm", resulting in certain limitations on the application scenarios of the method. In addition, the beta frequency band contains more spontaneous EEG components, which are easily affected by the subject's subjective or external environment.

[0006] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0007] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical components or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0008] The embodiments of the present disclosure provide a method, device and system for evaluating cognitive ability based on visual stimulation modulation, which improves the accuracy of brain-computer interface in evaluating cognitive ability.

[0009] In some embodiments, the method for evaluating cognitive ability based on visual stimulation modulation includes: collecting visual stimulation modulation EEG responses induced by the subject to be tested based on a control target and a cognitive target; wherein the visual stimulation modulation EEG responses characterize the response frequency generated by the steady-state visual evoked potential of the subject to be tested; determining the baseline spectrum energy corresponding to the control target in the visual stimulation modulation EEG responses, and the cognitive spectrum energy corresponding to the cognitive target in the visual stimulation modulation EEG responses; and using the baseline spectrum energy and the cognitive spectrum energy to evaluate the cognitive ability of the subject to be tested.

[0010] Optionally, the visual stimulation modulated EEG response induced by the subject to be tested based on the control target and the cognitive target is collected, including: based on the control target and the cognitive target, flickering interaction in a single-frequency manner to obtain the first visual stimulation modulated EEG response of the subject to be tested; and / or, based on the control target and the cognitive target, flickering interaction in a dual-frequency cross-modulation manner to obtain the second visual stimulation modulated EEG response of the subject to be tested.

[0011] Optionally, based on the control target and the cognitive target, the interaction is flashed in a single-frequency manner, including: selecting a grayscale block as the control target, and controlling the control target to flash at a first frequency at a set position; selecting a sign with specific cognitive characteristics as the cognitive target, and controlling the cognitive target to flash at a first frequency at a set position.

[0012] Optionally, based on the control target and the cognitive target, the interaction is flickering in a dual-frequency cross-modulation manner, including: selecting a grayscale color block as a control target, controlling the control target to flicker at a second frequency in front of the screen background, and controlling the screen background to flicker at a third frequency; selecting a sign with specific cognitive characteristics as a cognitive target, controlling the cognitive target to flicker at a second frequency in front of the screen background, and controlling the screen background to flicker at a third frequency.

[0013] Optionally, determining a baseline spectral energy corresponding to a control target in the visual stimulus modulated EEG response comprises: when the flicker frequency changes, determining the spectral energy that remains unchanged in the visual stimulus modulated EEG response as the baseline spectral energy; and / or determining a cognitive spectral energy corresponding to a cognitive target in the visual stimulus modulated EEG response comprises: when the flicker frequency changes, determining the spectral energy that fluctuates with the flicker frequency in the visual stimulus modulated EEG response as the cognitive spectral energy.

[0014] Optionally, the cognitive ability of the subject to be tested is evaluated using the baseline spectrum energy and the cognitive spectrum energy, including: obtaining the spectrum energy difference between the baseline spectrum energy and the cognitive spectrum energy; and evaluating the cognitive ability of the subject to be tested based on the spectrum energy difference and the spectrum energy threshold difference.

[0015] Optionally, using the baseline spectrum energy and the cognitive spectrum energy to evaluate the cognitive ability of the subject to be tested also includes: calculating the cognitive ability score of the subject to be tested in the following manner: when the spectrum energy difference is less than or equal to the spectrum energy threshold difference, reducing the cognitive ability score of the subject to be tested; when the spectrum energy difference is greater than the spectrum energy threshold difference, increasing the cognitive ability score of the subject to be tested; when the difference between the spectrum energy difference and the spectrum energy threshold difference is greater than the mean difference, increasing the cognitive ability score of the subject to be tested.

[0016] In some embodiments, the device for assessing cognitive ability based on visual stimulation modulation includes a processor and a memory storing program instructions, and the processor is configured to execute the method for assessing cognitive ability based on visual stimulation modulation as described above when running the program instructions.

[0017] In some embodiments, the system for assessing cognitive ability based on visual stimulation modulation includes: a task interaction terminal, configured to collect visual stimulation modulated EEG responses induced by the subject to be tested based on a control target and a cognitive target; wherein the visual stimulation modulated EEG responses represent the response frequency generated by the steady-state visual evoked potential of the subject to be tested; a data acquisition terminal, connected to the task interaction terminal, configured to determine the baseline spectrum energy corresponding to the control target in the visual stimulation modulated EEG responses, and the cognitive spectrum energy corresponding to the cognitive target in the visual stimulation modulated EEG responses; a data analysis terminal, connected to the data acquisition terminal, configured to use the baseline spectrum energy and the cognitive spectrum energy to assess the cognitive ability of the subject to be tested.

[0018] In some embodiments, the cognitive ability assessment device includes: an assessment device body; an apparatus for assessing cognitive ability based on visual stimulation modulation as described above, installed on the assessment device body; or a system for assessing cognitive ability based on visual stimulation modulation as described above, installed on the assessment device body.

[0019] The method, device and system for evaluating cognitive ability based on visual stimulation modulation provided by the embodiments of the present disclosure can achieve the following technical effects:

[0020] In the disclosed embodiment, inducing visual stimulation modulated EEG response of the subject to be tested can obtain the subject's cognition of the target. The control target and the cognitive target are two corresponding targets, so that the disclosed embodiment can induce visual stimulation modulated EEG response of the subject to be tested through the control target and the cognitive target respectively, so as to make a comparison to judge the cognitive ability of the subject to be tested. The disclosed embodiment can determine the reference spectrum energy and cognitive spectrum energy from the collected visual stimulation modulated EEG response, use the reference spectrum energy as the reference data, and use the cognitive spectrum energy to evaluate the cognitive ability of the subject to be tested. The disclosed embodiment uses the control target and the cognitive target as specific cognitive tasks, which can induce clearer feature markers in the brain signal of the subject to be tested, thereby reducing the influence of the subjective factors and external interference factors of the subject to be tested on the evaluation results, thereby improving the accuracy of the brain-computer interface in evaluating cognitive ability.

[0021] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein:

[0023] Figure 1 is a schematic diagram of an implementation environment of a method for assessing cognitive ability based on visual stimulation modulation according to an embodiment of the present disclosure;

[0024] Figure 2 is a schematic diagram of a method for assessing cognitive ability based on visual stimulation modulation provided by an embodiment of the present disclosure;

[0025] Figure 3 is a schematic diagram of another method for assessing cognitive ability based on visual stimulation modulation provided by an embodiment of the present disclosure;

[0026] Figure 4-1 It is a schematic diagram of a single-frequency method for inducing visual stimulation to modulate EEG response provided by an embodiment of the present disclosure;

[0027] Figure 4-2 It is a schematic diagram of a dual-frequency cross-modulation method provided by an embodiment of the present disclosure to induce visual stimulation to modulate EEG response;

[0028] Figure 5 is a schematic diagram of a device for assessing cognitive ability based on visual stimulation modulation provided by an embodiment of the present disclosure;

[0029] Figure 6Schematic diagram of a system for assessing cognitive ability based on visual stimulation modulation provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0031] The terms "first", "second", etc. in the technical solutions described in the embodiments of the present disclosure are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so as to describe the embodiments of the present disclosure described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0032] Unless otherwise stated, the term "plurality" means two or more.

[0033] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B indicates: A or B.

[0034] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0035] The term "correspondence" may refer to an association relationship or a binding relationship. The correspondence between A and B means that there is an association relationship or a binding relationship between A and B.

[0036] At present, the development of brain-computer interface technology in the field of cognitive ability assessment has provided a new direction for traditional psychological assessment methods. The brain-computer interface system collects EEG signals generated by brain activity in a non-invasive or invasive manner, and then processes and analyzes the EEG signals to identify specific signals to assess cognitive status or ability. The current cognitive ability assessment method that relies on brain-computer interface technology needs to collect more accurate EEG signals to reduce the impact of subjective factors and external interference factors on the assessment results.

[0037] Figure 1 Schematic diagram of the implementation environment of the method for assessing cognitive ability based on visual stimulation modulation according to an embodiment of the present disclosure. Figure 1As shown, the implementation environment may include a processor 500 , a task database 100 , an EEG cap 200 , and an EEG amplifier 300 .

[0038] Among them, the task database 100 stores relevant task materials for cognitive ability assessment. Cognitive ability assessment materials for more scenarios can be continuously iterated and expanded, such as videos, images, math problems, texts, etc. of different cognitive gradient tasks. The combination of materials and task trials in the task database 100 are all derived from the recommendations of cognitive ability judgment experts and classic literature in the field. The system selects the corresponding cognitive ability assessment task materials in the task database 100 according to the user's own needs, system suggestions or expert suggestions.

[0039] The EEG cap 200 can collect the EEG response modulated by visual stimulation of the subject to be tested by different collection methods such as wet electrodes, dry electrodes or semi-dry electrodes. The EEG amplifier 300 can amplify the collected EEG response modulated by visual stimulation and transmit the amplified signal to the processor 500. The processor 500 evaluates the cognitive ability of the subject to be tested based on the EEG response modulated by visual stimulation induced by the subject to be tested.

[0040] Combination Figure 2 As shown, the embodiment of the present disclosure provides a method for evaluating cognitive ability based on visual stimulation modulation, comprising:

[0041] S201, the processor collects visual stimulation-modulated electroencephalogram responses induced by the subject to be tested based on the control target and the cognitive target; wherein the visual stimulation-modulated electroencephalogram responses represent the response frequency generated by the steady-state visual evoked potential of the subject to be tested.

[0042] S202, the processor determines the reference spectrum energy corresponding to the control target in the EEG response modulated by visual stimulation, and the cognitive spectrum energy corresponding to the cognitive target in the EEG response modulated by visual stimulation.

[0043] S203: The processor evaluates the cognitive ability of the subject using the reference spectrum energy and the cognitive spectrum energy.

[0044] By adopting the method for evaluating cognitive ability based on visual stimulation modulation provided by the embodiment of the present disclosure, the visual stimulation modulation EEG response of the subject to be tested is induced to obtain the cognitive situation of the subject to be tested on the target. The control target and the cognitive target are two corresponding targets, so that the embodiment of the present disclosure can induce the visual stimulation modulation EEG response of the subject to be tested through the control target and the cognitive target respectively, so as to make a comparison to judge the cognitive ability of the subject to be tested. The embodiment of the present disclosure can determine the reference spectrum energy and the cognitive spectrum energy from the collected visual stimulation modulation EEG response, use the reference spectrum energy as the reference data, and use the cognitive spectrum energy to evaluate the cognitive ability of the subject to be tested. The embodiment of the present disclosure uses the control target and the cognitive target as specific cognitive tasks, which can induce clearer feature markers in the brain signal of the subject to be tested, thereby reducing the influence of the subjective factors and external interference factors of the subject to be tested on the evaluation results, thereby improving the accuracy of the brain-computer interface in evaluating cognitive ability.

[0045] Furthermore, the comparison target and cognitive target in the embodiment of the present disclosure may include various visual materials, such as videos, images, math problems, text, etc. It is convenient to combine with various existing professional scales or expert systems and has wider applicability.

[0046] Optionally, the visual stimulation modulated EEG response induced by the subject to be tested based on the control target and the cognitive target is collected, including: based on the control target and the cognitive target, flickering interaction in a single-frequency manner to obtain the first visual stimulation modulated EEG response of the subject to be tested; and / or, based on the control target and the cognitive target, flickering interaction in a dual-frequency cross-modulation manner to obtain the second visual stimulation modulated EEG response of the subject to be tested.

[0047] In the disclosed embodiment, the steady-state visual evoked potential generated by the visual cortex when the subject to be tested watches the control target and cognitive target flickering at a specific frequency is used to characterize the cognitive state. The cognitive ability is objectively evaluated by analyzing the EEG response of the subject to be tested to specific visual stimuli. Specifically, the system collects the EEG signals of the subject to be tested under single-frequency and / or dual-frequency cross-modulation stimulation, and the signals reflect the cognitive response of the subject to be tested to the stimulation. The system determines the baseline spectrum energy corresponding to the control target and the cognitive spectrum energy corresponding to the cognitive target by accurately measuring and analyzing specific spectral components in the EEG signals. By comparing the amplitude differences between the baseline and cognitive EEG spectrum components, the system can evaluate the cognitive abilities of the subject to be tested, such as attention, memory, and recognition ability. Single-frequency and / or dual-frequency cross-modulation can improve the accuracy and objectivity of the evaluation and reduce subjective bias.

[0048] Optionally, based on the control target and the cognitive target, the interaction is flashed in a single-frequency manner, including: selecting a grayscale block as the control target, and controlling the control target to flash at a first frequency at a set position; selecting a sign with specific cognitive characteristics as the cognitive target, and controlling the cognitive target to flash at a first frequency at a set position.

[0049] In the disclosed embodiment, suitable visual stimulation materials are selected, including grayscale blocks as control targets and signs with specific cognitive characteristics as cognitive targets. The materials can induce clear cognitive responses in the subject to be tested. By precisely controlling the frequency and content of the visual stimulation, EEG signals related to cognition are induced. When the human eye is fixated on light that flickers at a certain frequency, the visual cortex of the brain generates synchronous electrical activity. In practical applications, by selecting grayscale blocks as control targets and signs with specific cognitive characteristics as cognitive targets, flickering on the screen at a first frequency, the EEG response of the subject to be tested is induced. The single-frequency flickering interaction method can distinguish the cognitive responses of the subject to be tested to different visual stimuli, and then evaluate its cognitive ability.

[0050] Optionally, the first frequency, the second frequency and the third frequency are determined as follows: In the absence of any visual stimulation, the EEG signal for a period of time is collected as baseline data. The effects of different visual stimulation frequencies on the EEG response are simulated using simulation software. Based on the simulation results, the possible optimal induced frequency range is predicted. A series of frequency points are set, from low frequency to high frequency, and the actual visual stimulation sweep frequency experiment is performed on the participants. At each frequency point, the visual stimulation is presented for a certain period of time, and the EEG response is recorded. The collected EEG signal is preprocessed, including filtering, artifact removal and noise reduction. The spectral components of the EEG signal are analyzed using methods such as Fourier transform to determine the frequency points that can induce steady-state visual evoked potentials. According to the amplitude and signal-to-noise ratio of the steady-state visual evoked potential, the first frequency that induces the best frequency response is determined. For dual-frequency cross-modulation, the second frequency and the third frequency are determined, and the sum frequency or difference frequency of the second frequency and the third frequency show obvious characteristics in the visual stimulation modulation EEG response.

[0051] Optionally, based on the control target and the cognitive target, the interaction is flickering in a dual-frequency cross-modulation manner, including: selecting a grayscale color block as a control target, controlling the control target to flicker at a second frequency in front of the screen background, and controlling the screen background to flicker at a third frequency; selecting a sign with specific cognitive characteristics as a cognitive target, controlling the cognitive target to flicker at a second frequency in front of the screen background, and controlling the screen background to flicker at a third frequency.

[0052] In the disclosed embodiment, the control target and the cognitive target, as well as the background, are simultaneously presented on the screen. The control target and the cognitive target flicker at the second frequency, while the background flickers at the third frequency. In this way, an EEG response of dual-frequency cross-modulation can be induced. The collected EEG signal is preprocessed, such as filtering, amplification and noise reduction, and then the visual stimulus modulated EEG response related to the second frequency and the third frequency is extracted.

[0053] By simultaneously presenting two stimuli flickering at different frequencies on the screen, it is possible to more accurately detect and distinguish an individual's cognitive response to different visual stimuli, thereby providing an objective assessment of cognitive ability. The dual-frequency cross-modulation method can not only induce visual stimulus-modulated EEG responses associated with a single frequency, but also produce responses associated with the sum and difference frequencies between the two frequencies. It can provide richer EEG signal features, increase the dimension of assessment, enable the system to distinguish different cognitive states more finely, and improve the sensitivity and specificity of the assessment.

[0054] Optionally, determining a baseline spectral energy corresponding to a control target in the visual stimulus modulated EEG response comprises: when the flicker frequency changes, determining the spectral energy that remains unchanged in the visual stimulus modulated EEG response as the baseline spectral energy; and / or determining a cognitive spectral energy corresponding to a cognitive target in the visual stimulus modulated EEG response comprises: when the flicker frequency changes, determining the spectral energy that fluctuates with the flicker frequency in the visual stimulus modulated EEG response as the cognitive spectral energy.

[0055] In the disclosed embodiment, different flicker frequencies are set to collect visual stimulus modulation EEG responses induced by different flicker frequencies. When a mixed response of reference spectrum energy and cognitive spectrum energy is collected at the same time, the spectrum energy that remains unchanged is determined as the reference spectrum energy, and the spectrum energy that fluctuates with the flicker frequency is determined as the cognitive spectrum energy.

[0056] Optionally, the cognitive ability of the subject to be tested is evaluated using the baseline spectrum energy and the cognitive spectrum energy, including: obtaining the spectrum energy difference between the baseline spectrum energy and the cognitive spectrum energy; and evaluating the cognitive ability of the subject to be tested based on the spectrum energy difference and the spectrum energy threshold difference.

[0057] Combination Figure 3 As shown, the embodiment of the present disclosure provides another method for assessing cognitive ability based on visual stimulation modulation, comprising:

[0058] S301, the processor collects visual stimulation-modulated electroencephalogram responses induced by the subject to be tested based on the control target and the cognitive target; wherein the visual stimulation-modulated electroencephalogram responses represent the response frequency generated by the steady-state visual evoked potential of the subject to be tested.

[0059] S302, the processor determines the reference spectrum energy corresponding to the control target in the EEG response modulated by visual stimulation, and the cognitive spectrum energy corresponding to the cognitive target in the EEG response modulated by visual stimulation.

[0060] S303: The processor obtains a spectrum energy difference between the reference spectrum energy and the cognitive spectrum energy.

[0061] S304: The processor evaluates the cognitive ability of the subject to be tested according to the spectrum energy difference and the spectrum energy threshold difference.

[0062] In the embodiment of the present disclosure, the difference between the reference spectrum energy and the cognitive spectrum energy is calculated to evaluate the cognitive ability of the subject to be tested. If the spectrum energy difference exceeds the spectrum energy threshold difference, it indicates that the subject to be tested has a cognitive response to the cognitive target.

[0063] like Figure 4-1 As shown, the first frequency is f1, the control target and the cognitive target flicker at the first frequency, and the reference spectrum energy corresponding to the control target is collected as Amp base1. If the subject to be tested has a cognitive response to the cognitive target, the cognitive spectrum energy corresponding to the cognitive target collected will usually be higher than Amp base1, recorded as Amp yes1. If the subject to be tested does not have a cognitive response to the cognitive target, the cognitive spectrum energy corresponding to the cognitive target collected will usually be lower than Amp base1, recorded as Amp non1.

[0064] like Figure 4-2 As shown, the second frequency f2 and the third frequency f3 are superimposed as f2+f3, the control target flickers at the second frequency in front of the screen background, and the control screen background flickers at the third frequency, and the reference spectrum energy corresponding to the control target is collected as Amp base2. The cognitive target flickers at the second frequency in front of the screen background, and the control screen background flickers at the third frequency. If the subject to be tested has a cognitive response to the cognitive target, the cognitive spectrum energy corresponding to the cognitive target collected will usually be higher than Amp base2, recorded as Amp yes2. If the subject to be tested does not have a cognitive response to the cognitive target, the cognitive spectrum energy corresponding to the cognitive target collected will usually be lower than Amp base2, recorded as Amp non2.

[0065] Optionally, using the baseline spectrum energy and the cognitive spectrum energy to evaluate the cognitive ability of the subject to be tested also includes: calculating the cognitive ability score of the subject to be tested in the following manner: when the spectrum energy difference is less than or equal to the spectrum energy threshold difference, reducing the cognitive ability score of the subject to be tested; when the spectrum energy difference is greater than the spectrum energy threshold difference, increasing the cognitive ability score of the subject to be tested; when the difference between the spectrum energy difference and the spectrum energy threshold difference is greater than the mean difference, increasing the cognitive ability score of the subject to be tested.

[0066] In the disclosed embodiment, the cognitive ability score of the subject to be tested is calculated based on the spectrum energy difference and the preset threshold difference. Specifically, if the difference is less than or equal to the threshold difference, the score is reduced; if the difference is greater than the threshold difference, the score is increased; if the difference between the difference and the threshold difference is greater than the average difference, the score is increased. By setting the spectrum energy threshold difference, the specific score of the cognitive ability of the subject to be tested can be obtained, thereby providing a more detailed cognitive ability assessment. This provides a scientific basis for cognitive training and intervention of the subject to be tested, thereby improving the effectiveness of cognitive assessment and intervention.

[0067] For example, a set of tests includes 100 cognitive targets (including images, videos, formulas, etc. with different contents), and each image, video, and formula is regarded as a cognitive target. Each cognitive target combined with visually evoked frequency stimulation will obtain a spectral energy difference value. If the spectral energy difference value is less than or equal to the threshold difference value, it means that the cognitive target cannot be recognized, and 1 point is reduced. If the spectral energy difference value is greater than the threshold difference value, it means that the cognitive target can be recognized, and 1 point is increased. If the difference between the spectral energy difference value and the threshold difference value is greater than the mean difference value obtained based on a large sample (for example, by accumulating the result samples of 1,000 subjects to be tested, then the mean difference value based on 1,000 subjects to be tested can be obtained), an additional 0.2 points are added. Finally, a total score that can characterize the cognitive ability of the subject to be tested can be obtained.

[0068] Combination Figure 5 As shown, the embodiment of the present disclosure provides a device 50 for assessing cognitive ability based on visual stimulation modulation, including a processor (processor) 500 and a memory (memory) 501. Optionally, the device 50 may also include a communication interface (Communication Interface) 502 and a bus 503. Among them, the processor 500, the communication interface 502, and the memory 501 can communicate with each other through the bus 503. The communication interface 502 can be used for information transmission. The processor 500 can call the logic instructions in the memory 501 to execute the method for assessing cognitive ability based on visual stimulation modulation of the above embodiment.

[0069] In addition, the logic instructions in the memory 501 described above can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product.

[0070] The memory 501 is a computer-readable storage medium that can be used to store software programs and computer executable programs, such as program instructions / modules corresponding to the method in the embodiment of the present disclosure. The processor 500 executes the function application and data processing by running the program instructions / modules stored in the memory 501, that is, the method for evaluating cognitive ability based on visual stimulation modulation in the above embodiment is implemented.

[0071] The memory 501 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and an application required for at least one function; the data storage area may store data created according to the use of the terminal device, etc. In addition, the memory 501 may include a high-speed random access memory and may also include a non-volatile memory.

[0072] Combination Figure 6 As shown, the embodiment of the present disclosure provides a system 60 for evaluating cognitive ability based on visual stimulation modulation, including a task interaction terminal 601, and data acquisition terminals 602 and 603. The task interaction terminal 601 is configured to collect visual stimulation modulation EEG responses induced by the subject to be tested based on control targets and cognitive targets; wherein the visual stimulation modulation EEG responses represent the response frequency generated by the steady-state visual evoked potential of the subject to be tested. The data acquisition terminal 602 is connected to the task interaction terminal 601, and is configured to determine the reference spectrum energy corresponding to the control target in the visual stimulation modulation EEG responses, and the cognitive spectrum energy corresponding to the cognitive target in the visual stimulation modulation EEG responses. The data analysis terminal 603 is connected to the data acquisition terminal 602, and is configured to evaluate the cognitive ability of the subject to be tested using the reference spectrum energy and the cognitive spectrum energy.

[0073] The task interaction terminal 601 induces the visual stimulation modulated EEG response of the subject to be tested to obtain the subject's cognitive status of the target. The control target and the cognitive target are two corresponding targets, so that the embodiment of the present disclosure can induce the visual stimulation modulated EEG response of the subject to be tested through the control target and the cognitive target respectively, so that the data analysis terminal 603 compares to judge the cognitive ability of the subject to be tested. The data acquisition terminal 602 of the embodiment of the present disclosure can determine the reference spectrum energy and the cognitive spectrum energy from the collected visual stimulation modulated EEG response. The data analysis terminal 603 uses the reference spectrum energy as the control data and uses the cognitive spectrum energy to evaluate the cognitive ability of the subject to be tested. The embodiment of the present disclosure uses the control target and the cognitive target as specific cognitive tasks, which can induce clearer feature markers in the brain signal of the subject to be tested, thereby reducing the influence of the subjective factors and external interference factors of the subject to be tested on the evaluation results, thereby improving the accuracy of the brain-computer interface in evaluating cognitive ability.

[0074] The embodiments of the present disclosure provide a cognitive ability assessment device, including: an assessment device body, and the above-mentioned device for assessing cognitive ability based on visual stimulation modulation. The device for assessing cognitive ability based on visual stimulation modulation is installed on the assessment device body. The installation relationship described here is not limited to placement inside the assessment device body, but also includes installation connections with other components of the assessment device, including but not limited to physical connections, electrical connections, or signal transmission connections. It can be understood by those skilled in the art that the device 50 for assessing cognitive ability based on visual stimulation modulation can be adapted to a feasible assessment device body, thereby realizing other feasible embodiments.

[0075] The technical solution of the embodiment of the present disclosure can be embodied in the form of a software product, which is stored in a storage medium and includes one or more instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the embodiment of the present disclosure. The aforementioned storage medium may be a non-transient storage medium, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, and other media that can store program codes.

[0076] The above description and the accompanying drawings fully illustrate the embodiments of the present disclosure so that those skilled in the art can practice them. Other embodiments may include structural, logical, electrical, process and other changes. The embodiments represent only possible changes. Unless explicitly required, separate components and functions are optional, and the order of operation may vary. The parts and features of some embodiments may be included in or replace the parts and features of other embodiments. Moreover, the words used in this application are only used to describe the embodiments and are not used to limit the claims. As used in the description of the embodiments and the claims, unless the context clearly indicates, the singular forms of "a", "an" and "the" are intended to include plural forms as well. Similarly, the term "and / or" as used in this application refers to any and all possible combinations of listings containing one or more associated ones. In addition, when used in the present application, the term "comprise" and its variants "comprises" and / or comprising refer to the presence of stated features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the presence of other identical elements in the process, method or device comprising the elements. In this article, each embodiment may focus on the differences from other embodiments, and the same and similar parts between the various embodiments may refer to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, then the relevant parts can refer to the description of the method part.

[0077] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software may depend on the specific application and design constraints of the technical solution. The technicians may use different methods for each specific application to implement the described functions, but such implementations should not be considered to exceed the scope of the embodiments of the present disclosure. The technicians may clearly understand that, for the convenience and simplicity of description, the specific working processes of the systems, devices and units described above may refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here.

[0078] In the embodiments disclosed herein, the disclosed methods and products (including but not limited to devices, equipment, etc.) can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units can be only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between each other shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms. The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to implement this embodiment. In addition, each functional unit in the embodiment of the present disclosure may be integrated in a processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit.

[0079] The flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the embodiment of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and the block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in a different order from the order disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

Claims

1. A method for assessing cognitive ability based on visual stimulus modulation, characterized in that: include: Collecting the visual stimulation modulated electroencephalogram response induced by the subject to be tested based on the control target and the cognitive target; wherein the visual stimulation modulated electroencephalogram response represents the response frequency generated by the steady-state visual evoked potential of the subject to be tested; determining a baseline spectrum energy corresponding to a control target in an EEG response modulated by visual stimulation, and a cognitive spectrum energy corresponding to a cognitive target in an EEG response modulated by visual stimulation; The baseline spectrum energy and cognitive spectrum energy are used to evaluate the cognitive ability of the subject.

2. The method according to claim 1, characterized in that Collect the EEG responses modulated by visual stimulation induced by the subject based on the control target and cognitive target, including: Based on the control target and the cognitive target, flickering interaction in a single-frequency manner to obtain a first visual stimulus modulated EEG response of the subject to be tested; and / or, Based on the control target and the cognitive target, the flicker interaction is performed in a dual-frequency cross-modulation manner to obtain the EEG response modulated by the second visual stimulus of the subject.

3. The method according to claim 2, characterized in that Based on the control target and cognitive target, flicker interaction is performed in a single frequency manner, including: Selecting a grayscale color block as a control target, and controlling the control target to flash at a set position according to a first frequency; A sign with specific cognitive characteristics is selected as a cognitive target, and the cognitive target is controlled to flash at a set position according to a first frequency.

4. The method according to claim 2, characterized in that: Based on the control target and cognitive target, flicker interaction is performed in a dual-frequency cross-modulation manner, including: Selecting a grayscale color block as a control target, controlling the control target to flicker at a second frequency in front of the screen background, and controlling the screen background to flicker at a third frequency; A sign with specific cognitive characteristics is selected as a cognitive target, the cognitive target is controlled to flash at a second frequency in front of a screen background, and the screen background is controlled to flash at a third frequency.

5. The method according to claim 1, characterized in that Determine the baseline spectral energy in the EEG response modulated by the visual stimulus relative to the control target, including: When the flicker frequency changes, the spectral energy that remains unchanged in the EEG response modulated by visual stimulation is determined as the baseline spectral energy; and / or, Determine the cognitive spectral energy corresponding to the cognitive target in the EEG response modulated by visual stimuli, including: When the flicker frequency changes, the spectral energy in the EEG response modulated by visual stimulation that fluctuates with the flicker frequency is determined as cognitive spectral energy.

6. The method according to any one of claims 1 to 5, characterized in that: The baseline spectrum energy and cognitive spectrum energy are used to evaluate the cognitive ability of the subject, including: Obtaining a spectrum energy difference between a reference spectrum energy and a cognitive spectrum energy; The cognitive ability of the subject to be tested is evaluated based on the spectrum energy difference and the spectrum energy threshold difference.

7. The method according to claim 6, characterized in that The reference spectrum energy and cognitive spectrum energy are used to evaluate the cognitive ability of the subject to be tested, and also include: The cognitive ability score of the subjects was calculated as follows: When the spectrum energy difference is less than or equal to the spectrum energy threshold difference, reducing the cognitive ability score of the subject to be tested; When the spectrum energy difference is greater than the spectrum energy threshold difference, the cognitive ability score of the subject to be tested is increased; When the difference between the spectrum energy difference value and the spectrum energy threshold difference value is greater than the mean difference value, the cognitive ability score of the subject to be tested is increased.

8. A device for assessing cognitive ability based on visual stimulus modulation, comprising a processor and a memory storing program instructions, characterized in that: The processor is configured to execute the method for assessing cognitive ability based on visual stimulation modulation according to any one of claims 1 to 7 when running the program instructions.

9. A system for assessing cognitive ability based on visual stimulus modulation, characterized in that: include: The task interaction terminal is configured to collect visual stimulation-modulated electroencephalogram responses induced by the subject to be tested based on the control target and the cognitive target; wherein the visual stimulation-modulated electroencephalogram responses represent the response frequency generated by the steady-state visual evoked potential of the subject to be tested; A data acquisition terminal connected to the task interaction terminal and configured to determine a baseline spectrum energy corresponding to a control target in the EEG response modulated by visual stimulation, and a cognitive spectrum energy corresponding to a cognitive target in the EEG response modulated by visual stimulation; The data analysis terminal is connected to the data acquisition terminal and is configured to evaluate the cognitive ability of the subject using the reference spectrum energy and the cognitive spectrum energy.

10. A cognitive ability assessment device, characterized in that: include: Evaluate the equipment itself; The apparatus for assessing cognitive ability based on visual stimulation modulation as claimed in claim 8, mounted on the assessment device body; Alternatively, the system for assessing cognitive ability based on visual stimulation modulation as claimed in claim 9 is installed in the assessment device body.

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