WO2021085772A1

WO2021085772A1 - Method and apparatus for assessing degenerative cognitive decline on basis of eye movement

Info

Publication number: WO2021085772A1
Application number: PCT/KR2020/006198
Authority: WO
Inventors: 김중일; 김재욱; 오펀야줄리어스
Original assignee: 한국 한의학 연구원
Priority date: 2019-10-31
Filing date: 2020-05-11
Publication date: 2021-05-06
Also published as: KR102324372B1; KR20210052043A

Abstract

Disclosed are a method for assessing degenerative cognitive decline on the basis of eye movement and an apparatus for evaluating degenerative cognitive decline on basis of eye movement. According to one embodiment of the present invention, a method for evaluating degenerative cognitive decline on the basis of eye movement comprises the steps of: analyzing forward and reverse saccadic eye movements of eyeballs for tracking a moving target; measuring an error rate regarding a degree of deviation of the movement of the eyeballs from the movement path of the target through the analysis; measuring a response delay time required for the eyeballs to track the target in a predetermined interval in which the target moves through the analysis; and when any one of the error rate and the response delay time is greater than or equal to a predetermined threshold value, determining that a subject who recognizes an object through the eyeballs has cognitive decline.

Description

Method and device for evaluating degenerative cognitive decline based on eye movement

In the present invention, in objectively evaluating the decline in brain cognitive function by quantifying the intermittent eye movement in the forward/reverse direction, the incorrect answer rate (accuracy), response delay time, and pupil size change are used as cognitive function evaluation variables, and these The present invention relates to a method and apparatus for evaluating degenerative cognitive decline based on eye movement, which evaluates the degree of cognitive decline by combining cognitive function evaluation variables.

The eyeball can be exercised through the ocular muscle consisting of 6 extraocular muscles, 4 rectus muscles, and 2 oblique muscles in human anatomy, and neurophysiologically, it is exercised by the control mechanisms of the complex cranial nervous system including the inner nerves. However, degeneration of the brain's nervous system may affect not only cognitive functions such as memory, judgment, concentration, etc. but also the nervous system involved in eye movement, resulting in ocular movement disorders. These eye movement disorders can be linked to early symptoms of degenerative brain diseases such as Alzheimer's disease, vascular dementia, Lewy body dementia, and Parkinson's disease. Eye movement evaluation can be helpful for early diagnosis of cranial and nervous system diseases, and can be used as a non-invasive and constant monitoring index.

Eye movement moves the current gaze to an object of interest (gaze shift) so that the image is formed in the fovea, a saccade, vergence, and the image formed in the fovea is not shaken. It can be divided into vestibular eye movement, smooth pursuit, optokinetic eye movement, and visual fixation, which stabilizes and secures clear vision. In particular, intermittent eye movements, which play an important role in daily life, such as reading text or exploring the surroundings, are possible through conjugate eye movements by horizontality, verticality, and convolution. These eye movements can be observed directly with the naked eye, or by the examiner using glasses with high refractive lenses (Frenzel glasses), or the safety level (EOG, electro-oculography) using the voltage difference between electrodes attached to the left and right or upper and lower sides of the eyeball. ) Or using an infrared camera. Recently, it is possible to measure the bio-signal of eye movement according to the visual stimulus presented by using an eye tracking device, and thus, it is used in various studies to analyze eye movement and eye gaze patterns.

Intermittent eye movement is the fastest movement among eye movements, by presenting a specific visual stimulus in the forward/reverse direction and measuring the biosignal of the eye movement that changes in pursuit of the target, and the subject's eye movement direction, response rate, and response to the target. It can be used to evaluate delay time, pupil size change, etc. For the forward/reverse intermittent eye movement task, the subject must see the target of the presented visual stimulus and move the eyeball in the promised direction, so when the target of the visual stimulus is presented, attention needs to be paid, depending on the direction in which the target is presented. Judgment to implement and suppress eye movements may be required.

When performing the forward/reverse intermittent eye movement task, the subject's eye movement is neurophysiologically possible by the cranial nervous system regulation mechanisms of the frontal and parietal lobes including the inner nerves, and the brain involved in this intermittent eye movement function. The area of may be similar to that of the brain responsible for the executive function of selective attention and cognitive inhibitory. For example, patients with degenerative brain diseases such as mild cognitive impairment, Alzheimer's disease, Parkinson's disease, etc. have significant differences compared to healthy subjects such as decrease in intermittent eye movement speed, prolonged response delay, decrease in accuracy, and change in pupil size. This can be explained by a decrease in attention span and a lack of inhibitory function.

In addition, the change in pupil size is affected by the autonomic nervous system regulation of the sympathetic and parasympathetic nervous system due to the enlargement of the pupil by the adrenaline neurotransmission or the reduction of the pupil by the acetylcholine neurotransmission. In the case of, studies have been reported that it is possible to predict the risk of dementia by analyzing the pupil response. For example, in the case of mild cognitive impairment whose brain cognitive function is the same or similar to the normal group, the pupil is enlarged when performing a cognitive function task in the mild cognitive impairment patient group, showing a difference from the normal group, and the change in pupil size also decreases cognitive function It has been reported as a useful index for early diagnosis of patients with mild cognitive impairment and dementia whose main symptoms are.

The possibility of early diagnosis of brain diseases using eye movement is very high, and research is being conducted mainly in advanced countries such as the United States, Japan, and China, so development of eye movement-based brain aging quantification technology suitable for the characteristics of Koreans is required.

To this end, a cohort study is required to identify the pathogenesis factors of normal, mild cognitive impairment, and dementia through large-scale sample group tracking, and to determine the level of functional aging and degeneration of eye movements. The development of algorithms and analysis techniques that can objectively evaluate degenerative cognitive decline through clinical research is needed to discover biomarkers of eye movements that have a significant association with risk dialectic indicators.

In addition, it can be used in subsequent studies related to the clinical diagnosis and treatment technology development of diseases with cognitive decline as the main symptom in future oriental and Western fusion studies, so it is required to evaluate cognitive decline with a new evaluation technique based on eye movement. do.

An embodiment of the present invention is to design an algorithm for inducing and evaluating the activity of high-level cognitive function in the intermittent eye movement in the forward/reverse direction, and the movement direction of the eyeball, the error rate, and the latency of the response. ) And pupil size variation as an objective evaluation variable, the purpose of which is to provide a method and apparatus for evaluating degenerative cognitive decline based on eye movement, which evaluates cognitive decline.

In addition, the embodiment of the present invention tracks the movement of the eyeball and allows it to be used as a clinical diagnostic tool in diseases such as mild cognitive disorder and dementia, which have cognitive decline as the main symptom, The purpose of this study is to resolve the subjective ambiguity of the examiner and the examinee in the clinical field evaluating the decline in function.

According to an embodiment of the present invention, a method for evaluating degenerative cognitive decline based on eye movement includes: analyzing forward and reverse intermittent eye movements of the eyeball for tracking a moving target; Measuring an incorrect answer rate regarding a degree of deviation of the movement of the eyeball from the movement path of the target through the analysis; Measuring a response delay time required for the eyeball to track the target in a predetermined section in which the target moves through the analysis; And when any one of the incorrect answer rate and the response delay time is greater than or equal to a predetermined threshold value, determining a cognitive decline for a subject who recognizes an object through the eyeball.

In addition, according to an embodiment of the present invention, the apparatus for evaluating degenerative cognitive decline based on eye movement includes: an analysis unit for analyzing forward and reverse intermittent eye movements of an eyeball for tracking a moving target; Through the analysis, the rate of incorrect answer regarding the degree to which the movement of the eyeball deviates from the movement path of the target is measured, and in a predetermined section in which the target moves, the response required for the eyeball to track the target A measuring unit for measuring a delay time; And a determination unit for determining a decrease in cognitive function for a subject who recognizes an object through the eye when any one of the incorrect answer rate and the response delay time is greater than or equal to a predetermined threshold value.

According to an embodiment of the present invention, in the forward/reverse intermittent eye movement, an algorithm for inducing and evaluating the activity of high cognitive function is designed, and the movement direction of the eyeball, the wrong answer rate, the response delay time, and the pupil size change By using as an objective evaluation variable, it is possible to provide a method and apparatus for evaluating degenerative cognitive decline based on eye movement, which evaluates cognitive decline.

In addition, according to an embodiment of the present invention, by tracking the movement of the eyeball, the existing questionnaire can be used as a clinical diagnostic tool in diseases such as mild cognitive disorder and dementia, which have cognitive decline as the main symptom. Through this, the subjective ambiguity of the examiner and the examinee in the clinical field evaluating cognitive decline can be resolved.

1 is a block diagram showing the configuration of an apparatus for evaluating degenerative cognitive decline based on eye movement according to an embodiment of the present invention.

2 is a view showing an example of the measurement posture of the eye movement test according to the present invention.

3 is a view showing an example of the presentation time of the eye movement test visual stimulation according to the present invention.

4 is a diagram for explaining a process of interpreting a result of intermittent eye movement in relation to the determination of cognitive decline according to the present invention.

5 is a flowchart illustrating a method for evaluating degenerative cognitive decline based on eye movement according to an embodiment of the present invention.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, since various changes may be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It is to be understood that all changes, equivalents, or substitutes to the embodiments are included in the scope of the rights.

The terms used in the examples are used for illustrative purposes only and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present specification, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof does not preclude in advance.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiment belongs. Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in the present application. Does not.

In addition, in the description with reference to the accompanying drawings, the same reference numerals are assigned to the same components regardless of the reference numerals, and redundant descriptions thereof will be omitted. In describing the embodiments, when it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the embodiments, the detailed description thereof will be omitted.

Referring to FIG. 1, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement according to an embodiment of the present invention includes an analysis unit 110, a measurement unit 120, and a determination unit 130. Configurable. In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may be configured by adding a processing unit 140 according to an exemplary embodiment.

First, the analysis unit 110 analyzes the forward and reverse intermittent eye movements of the eyeball tracking the moving target. That is, the analysis unit 110 may serve to analyze that the target exposed to the test subject moves at a set speed in a designated section, and thus the test subject moves the eyeball to follow the target.

The forward intermittent eye movement (Prosaccade) of the eyeball is a movement obtained by allowing the subject to look at the target in the same direction as the moving direction of the target, and can be used as an index to test the test subject's simple reaction ability.

On the other hand, the reverse intermittent eye movement (Antisaccade) of the eyeball is a movement obtained by allowing the subject to look at the target in the direction opposite to the direction of movement of the target, and measures direction error and saccade latency. It is used as an index to evaluate the test subject's cognitive information processing ability.

In the present invention, among the intermittent eye movement tasks of the eyeball, the use of a task in which the forward/reverse ratio is in a ratio of 1:1 to 3:1 is exemplified.

Through the analysis, the measurement unit 120 measures an incorrect answer rate regarding the degree to which the movement of the eyeball deviates from the movement path of the target. That is, the measurement unit 120 may serve to measure the difference between the tracking path according to the forward/reverse intermittent eye movement of the eyeball and the actual movement path of the target by converting it as a ratio.

For example, in tracking a target that moves 20 times in a reciprocating direction in a predetermined section with a task combined with a forward/reverse ratio of 3:1, the measurement unit 120 is at the time of 15 forward intermittent eye movements, An incorrect answer rate of '13.3%' when the number of eye movements and the number of deviations from the target movement path is '2', and the number of movements of the eyeball and the number of deviations from the movement path of the target during 5 reverse intermittent eye movements When is '1', the incorrect answer rate can be measured as '20.0%', and the number of movements of the eyeball and the number of deviations from the movement path of the target during intermittent eye movement in the forward/reverse direction becomes '3'. It can be measured with an incorrect answer rate of '15.0%'.

In measuring the incorrect answer rate, the measurement unit 120 may correct the incorrect answer rate by assigning a predetermined weight according to the intermittent forward/reverse eye movement of the eyeball.

In the above example, under the assumption that the incorrect answer rate for the reverse intermittent eye movement is more important to the evaluation of cognitive decline than the incorrect answer rate for the forward intermittent eye movement, the measurement unit 120 is used for the reverse intermittent eye movement. The incorrect answer rate ((0.133+(0.2*1.1))/(1+1.1)*100=16.8%) can be calibrated and measured by adding a weight of 1.1 to the wrong answer rate.

That is, when the wrong answer rate of the forward intermittent eye movement is'E _P ', the wrong answer rate of the reverse intermittent movement is'E _A ', and the weight of the wrong answer rate is'W _E ', the measurement unit 120 ) Can correct and measure the incorrect answer rate through the conversion formula'(E _P +E _A *W _E )/(1+W _{E) *100'.}

In addition, the measurement unit 120 measures a response delay time required for the eyeball to track the target in a predetermined section in which the target moves. That is, the measurement unit 120 may measure a delay time required for tracking the target with the eyeball in response to the target after starting to move in a predetermined section as the response delay time.

For example, in tracking a target that moves 20 times in a reciprocating direction in a predetermined section with a task combined with a forward/reverse ratio of 3:1, the measurement unit 120 is at the time of 15 forward intermittent eye movements, The average delay time of the eyeball can be measured as '0.4 seconds' and the average delay time of the eyeball at the time of 5 reverse intermittent eye movements, and the average delay time of the eyeball at '0.5 seconds'. The average delay time of '0.42 seconds' can be measured as the response delay time.

In the measurement of the response delay time, the measurement unit 120 may correct the response delay time by assigning a predetermined weight according to the intermittent forward/reverse eye movement of the eyeball.

In the above example, under the assumption that the average delay time for the reverse intermittent eye movement is higher than the average delay time for the forward intermittent eye movement, the measurement unit 120 is The response delay time ((0.4+(0.5*1.1))/(1+1.1)=0.452) can be calibrated and measured by adding a weight of 1.1 to the average delay time related to exercise.

That is, when the response delay time of the forward intermittent eye movement is'L _P ', the response delay time of the reverse intermittent eye movement is'L _A ', and the weight of the response delay time is'W _L ', The measurement unit 120 may calibrate and measure the response delay time through the _{conversion formula'(L P} +L _A *W _L )/(1+W _{L )'.}

When any one of the incorrect answer rate and the response delay time is greater than or equal to a predetermined threshold, the determination unit 130 determines a cognitive decline for the test subject who recognizes an object through the eyeball. That is, the determination unit 130 compares each of the previously measured incorrect answer rate and response delay time with a threshold value, and if any one of the incorrect answer rate or response delay time is equal to or greater than the threshold value, the test subject's cognitive function It can be judged that there is something wrong.

The threshold value may be selected by appropriately adjusting the wrong answer rate and response delay time obtained in the normal aging group (group with normal cognitive function) in consideration of the environment for implementing the invention.

For example, when the threshold values of the incorrect answer rate and the response delay time are selected as 20% and 0.3 seconds, respectively, the determination unit 130 confirms that the previously measured incorrect answer rate 25% is greater than or equal to the threshold value of 20%, and Decreased cognitive function can be judged.

In the selection of the threshold value, the apparatus 100 for evaluating degenerative cognitive function based on eye movement adds the processing unit 140 as a configuration, so that the incorrect answer rate and response delay obtained in the normal aging group by the processing unit 140 Through arithmetic processing for time, it is possible to select a threshold value.

The processing unit 140 calculates an average and a standard deviation of response delay times for each of the reverse intermittent eye movement and the forward intermittent eye movement in the normal no-go group selected in advance, and the average and the standard deviation By using, it can be selected as the threshold value to be compared with the response delay time. That is, the processing unit 140 obtains the mean (Mean) and standard deviation (SD) of the response delay time for the intermittent eye movement of the group member in the group from the group whose eye movement is determined to be normal. Can play a role.

In addition, the processing unit 140 calculates the average and standard deviation of the wrong answer rates for the reverse intermittent eye movement in the normal no-go group selected in advance, and using the average and the standard deviation, the incorrect answer rate and the It can be selected as the threshold value to be compared. That is, the processing unit 140 is the average and standard of the response delay time for the reverse intermittent eye movement among the intermittent eye movements of the group members within the group from the group whose eye movement is determined to be normal. It can play a role of finding the deviation (SD).

After obtaining the average and the standard deviation, the processor 140 may select a result of calculating the'average + 1.5 * standard deviation' as the threshold value. That is, the processing unit 140 may select a value obtained by adding an average to a standard deviation to which a weight of '1.5' is assigned, as a threshold value for an incorrect answer rate and a response delay time.

In another embodiment, when both the incorrect answer rate and the response delay time are less than the threshold value, the analysis unit 110 analyzes the change in the size of the pupil in the eyeball. That is, even if both the previously measured incorrect answer rate and response delay time are less than the threshold value, the analysis unit 110 may additionally analyze the change in the size of the pupil without determining that the cognitive function is normal.

Through this, the analysis unit 110 may make the determination of the decrease in cognitive function of the test subject more accurately.

In the change in the size of the pupil, the analysis unit 110 may present a visual stimulus to the viewing range of the eyeball. Here, the visual stimulation is a FIXATION stimulation to fix the eyeball, CUE stimulation to distinguish forward and reverse intermittent eye movements, GAP stimulation to control the response effect to the presentation of target stimulation, forward and reverse intermittent eyeballs. It can consist of TARGET stimulation to move the position of the target according to the movement.

The analysis unit 110 may present visual stimulation in the order of the FIXATION stimulation, the CUE stimulation, the GAP stimulation, and the TARGET stimulation.

Thereafter, the analysis unit 110 may analyze a change in the size of the pupil between a time point at which the CUE stimulation is presented and a time point just before the GAP stimulation is presented in the field of view. That is, the analysis unit 110 may check the pupil at the point where the intermittent eye movement changes from the forward direction to the reverse direction and the pupil at the point immediately before the eyeball adapts according to the direction change, and analyze the changing size. .

In addition, the determination unit 130 determines a detailed state of the cognitive decline in consideration of the change in the size of the pupil. That is, the determination unit 130 may determine a specific state for the decrease in cognitive ability of the test subject by checking to which grade the change in the pupil size falls within the selected range.

The range is configured to include a plurality of grades, and the determination unit 130 determines the detailed state of the cognitive decline according to the grade within the range to which the change in the size of the pupil belongs,'the initial stage of cognitive decline'. ,'Memory cognitive decline stage', and'high-risk stage of cognitive decline'.

That is, the determination unit 130 may identify a specific grade within a range corresponding to a change in the size of the pupil, and recognize in detail a state of cognitive decline corresponding to the identified grade.

For example, when a change in the size of the pupil identified between the time point at which the CUE stimulation is presented and the time point immediately before the GAP stimulation is presented in the field of view falls within the second grade within the range, the determination unit 130 may determine the 2 The'memory cognitive decline stage' corresponding to the fourth grade can be determined as a detailed state of the test subject.

The apparatus for evaluating degenerative cognitive decline based on eye movement 100 evaluates cognitive function and concentration reduction by quantifying the characteristics of eye movement through a task of measuring intermittent eye movement of the eyeball.

The apparatus for evaluating degenerative cognitive decline based on eye movement 100 combines the ratio of forward and reverse intermittent eye movements in a 1:1 ratio to 3:1 ratio among the intermittent eye movement tasks of the eyeball. You can use the old assignments.

The apparatus 100 for evaluating degenerative cognitive decline based on eye movement may evaluate an incorrect answer rate, response delay time, cognitive function based on changes in pupil size, memory and concentration decline as cognitive function evaluation variables.

In degenerative aging accompanied by cognitive decline compared to natural aging, an increase in the wrong answer rate, an increase in response delay time, and a change in the size of the pupil can provide meaningful information.

The task of intermittent eye movement can be repeatedly performed in the order of a fixed gaze point, a guide indicating whether it is a forward or reverse intermittent eye movement, and a gaze point.

The category of response delay time is classified into, for example, predicted delay time (anticipatory), rapid delay time (express, short-latency stimulus-driven saccades), and regular-latency saccade, and as a cognitive function evaluation analysis variable Normal delay time can be used.

Here, the predicted delay time may be 80 to 100 ms, the rapid delay time may be 90 to 140 ms, and the normal delay time may be greater than 140 ms.

In determining cognitive decline, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine cognitive decline for the test subject if the incorrect answer rate is high or the response delay time is long.

If there is no significant difference in the rate of incorrect answers or response delay time, it can be judged as an early stage of cognitive decline or a high risk of cognitive decline when the degree of pupil relaxation is severe.

The apparatus 100 for evaluating degenerative cognitive decline based on eye movement is between the time point when a CUE indicating the condition of the task (eg, whether it is a forward intermittent eye movement or a reverse intermittent eye movement) is given and a time point before the stimulus appears. Changes in the size of the pupil can be observed.

For patients whose incorrect answer rate or response delay time falls within the normal range, the apparatus 100 for evaluating degenerative cognitive decline based on eye movements, if the size of the pupil is larger than that of the normal person, the initial phenomenon of cognitive decline or a high risk of decline It can be judged by the state.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may analyze a success rate, a response delay time, a response magnitude, and a maximum eye movement velocity. If the test subject has poor cognitive ability, the delay time increases, the magnitude of the response and the maximum speed of eye movement decrease, and the lower the cognitive ability, the lower the correct answer rate.

According to an embodiment, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may analyze micro saccades and Square Wave Jerks in a fixation to determine whether there is a symptom of dementia. Can be judged.

Here, the forward intermittent eye movement may be an exercise that maintains the gaze at the position of the stimulus by moving the gaze in the direction in which the stimulus presented from the basic point is located. This forward intermittent eye movement is a simple exercise that does not require a high executive function, and it is possible to predict the decrease in volume of the parietal lobe, which is related to visual attention due to the decline in Alzheimer's (AD) function.

In addition, the reverse intermittent eye movement may be an exercise in which a gaze is moved in a direction opposite to a position of a stimulus presented at a basic point to maintain a gaze at a position opposite to the stimulus. These reverse intermittent eye movements have a longer latency as cognitive ability decreases, and have a good correlation with the results of mild cognitive impairment (MCI), dementia, and executive function in the healthy group. It can reflect that the executive function became difficult due to the initial phenomenon of functional decline.

The apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine the decline in cognitive function for the test subject when it exceeds a predetermined threshold value in the incorrect answer rate and response delay time.

For example, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine the test subject as cognitive decline if the wrong answer rate based on the reverse intermittent eye movement is 50.5% or more.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine the subject as cognitive decline if the response delay time based on the forward intermittent eye movement is 326 ms or more.

In the task of forward/reverse intermittent eye movement, in the criterion for cognitive decline based on the change in the size of the pupil, the eye movement-based degenerative cognitive decline evaluation device 100 gave the CUE to inform the condition of the eye movement task. It is possible to observe the change in the size of the pupil, which changes between the time point before the appearance of the stimulus point and the stimulus point.

If the observed pupil dilation is more than a predetermined threshold, the eye movement-based degenerative cognitive decline evaluation apparatus 100 may determine a patient at high risk of cognitive decline or an initial symptom of cognitive decline.

The specific threshold may vary depending on the task condition, and may be defined as 0.063 mm or more as a standard for reverse intermittent eye movement.

The apparatus 100 for evaluating degenerative cognitive decline based on eye movement analyzes the results obtained from the forward/reverse intermittent eye movement task in the judgment of determining cognitive decline based on the eye movement biosignal, and the incorrect answer rate is specified. When it increases above the threshold value, or when the delay degree of the response delay time in the normal response delay time interval increases above a specific threshold value, it may be determined as cognitive decline.

In addition, when the incorrect answer rate does not exceed a specific threshold value and the delay degree of the response delay time in the normal response delay time section does not exceed a specific threshold value, the eye movement-based degenerative cognitive decline evaluation device 100 changes the size of the pupil. By additionally analyzing the pupil size, it is possible to determine detailed conditions related to cognitive decline, such as the initial stage of cognitive decline, memory cognitive decline stage, and high-risk stage of cognitive decline, if the change in pupil size increases beyond a certain threshold. .

The apparatus 100 for evaluating degenerative cognitive decline based on eye movement may be compared with an eye movement biosignal database presenting a reference score in determining the deterioration of high-level cognitive function based on the eye movement biosignal.

During the forward/reverse intermittent eye movement task, the criteria for declining cognitive decline in the direction of eye movement, the rate of incorrect answer, the response delay time, and the rate of change in pupil size according to the visual stimulation presented are as shown in [Table 1].

In determining cognitive decline, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement sets the'average + 1.5 x standard deviation' of the normal aging group as a threshold value as the reference score of the incorrect answer rate and delay time. If the score is exceeded, it can be judged as cognitive decline.

In calculating the change in the size of the pupil, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement is the size of the pupil that changes between the time point where the CUE (indicator point) is given and the time point before the stimulus point appears. You can calculate the change. The specific threshold to be used when the pupil size is changed may be, for example, 0.063 mm in the reverse intermittent eye movement.

In the apparatus 100 for evaluating degenerative cognitive decline based on eye movement, it is possible to design an algorithm for inducing and evaluating high-level cognitive function activity through a forward/reverse intermittent eye movement task.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movements is based on attention control, cognitive suppression, inhibition control, and cognitive flexibility based on the presentation of visual stimuli. In order to induce the activation of the function, it is possible to perform intermittent forward/reverse eye movements.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine a form and condition of a visual stimulus to be presented to a subject in the forward/reverse intermittent eye movement.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may measure and analyze the eye movement bio-signals of the test subject in response to the visual stimulus using the eye tracking device.

In addition, the eye movement-based degenerative cognitive decline evaluation device 100 evaluates the test subject's eye movement bio-signals (eye movement direction, response delay time, error rate, pupil size change rate) by comparing it with a reference score for determining the decrease in cognitive function. I can.

In determining the decline in cognitive function, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement is compared with the true value criterion of the eye movement response after presentation of the visual stimulation according to the presentation condition of the target visual stimulation in the forward/reverse intermittent eye movement. Eye movement bio-signals corresponding to the true value can be analyzed.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement meets the criterion score for determining cognitive decline in the eye movement response after presentation of the visual stimulus by analyzing the true value of the eye movement biosignal, and the pupil size change rate is also within the threshold value. It can be determined as a normal aging group.

On the other hand, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine a cognitive decline and a high risk group for dementia when the accuracy or response delay time of the eye movement response is less than or equal to the reference score.

In addition, the eye movement-based degenerative cognitive decline evaluation device 100, if the accuracy of the eye movement response or the response delay time meets the reference score, based on the change in the size of the pupil to the visual stimulus, cognitive decline risk group, mild recognition It can be identified as a hypodermic syndrome.

The forward/reverse intermittent eye movement is a high level of attention to the target stimulus presented as a visual stimulus and the decision-making and problem solving to plan, implement or suppress the eye movement in the direction of the target stimulus presentation. It may be related to cognitive activity.

Eye movement is the cerebral cortex of the frontal eye field (FEF), parietal eye field (PEF), supplementary eye field (SEF), and dorsolateral prefrontal cortex (DLPFC). It can be regulated by the area and the inner nerve.

High-level cognitive functions such as planning, decision making, problem solving, and behavioral control include the frontal cortex (FC), the anterior cingulate cortex (ACC), and the orbitofrontal cortex (OCR). ) It can be a complex cerebral nerve activity centered on.

Damage to the cerebral frontal lobe due to trauma or damage to the frontal lobe function due to degenerative neurological diseases such as dementia, stroke, and Parkinson's disease can lead to defects in high-level cognitive functions such as planning ability, decision-making ability, problem solving ability, and behavioral control, and Overlapping with the regulating nerve pathways, changes in visual perception movement can reduce eye movement ability. Intermittent eye movement and brain cognitive function have a high neurophysiological correlation.

2A illustrates the height/length/angle values required for observing the eye movement of the test subject after the subject is seated in front of the eye tracking device embodying the present invention.

The eye tracking device may be implemented on an electric desk that can be adjusted in height, and the adjustable height may be 70 to 120 cm.

The position of the subject's face as viewed from the eye tracking device may be within 35 degrees, and the subject seated in the chair puts his face on the bib, and in response to the visual stimulus presented by the eye tracking device, the eyeball performs intermittent eye movement. .

In FIG. 2B, it is exemplified that the distance between the eye tracking device and the test subject is about 100 cm, and the distance between the eye tracking device and the bib is about 65 cm.

Eye movement bio-signals can be measured with eye tracking equipment for the eye movement of the subject during the time when the visual stimulus is presented based on the size of the visual stimulus presentation screen "width 1920 × height 1680 px".

The measured eye movement can be obtained by obtaining x and y two-dimensional time series coordinate data and the size of the pupil as information in units of pixels (pixels, px).

For the eye movement of the subject in response to the visual stimulation, an area of interest (AOI) with a radius of 104px (2.5°) is designated around each visual stimulation position, and the subject's gaze reaches within the area of interest after the TARGET stimulation is presented. Behavioral responses can be judged as true values.

In the forward/reverse intermittent eye movement task, the true value of the eye movement response after the presentation of the TARGET stimulus is, the first movement of the gaze moves in the direction of the promised target (forward or reverse), and the response delay time of the gaze is after 80 msec, and 600 msec. It can be judged as a true value only if it is within the AOI and keeps the gaze at least 100msec (fixed gaze) within the AOI.

The eye movement bio-signals measured through the eye tracking device can be compared with the reference score (threshold) by the eye movement direction, incorrect answer rate, response delay time, and pupil size change rate of the subject who responded to the presentation of the visual stimulus.

The visual stimulation of forward/reverse intermittent eye movement is FIXATION stimulation to fix the gaze, CUE stimulation to distinguish forward/reverse intermittent eye movement conditions, GAP stimulation to control the response effect to target stimulus presentation, forward/reverse direction. It can be composed of TARGET stimulation to move the gaze to the target according to the intermittent eye movement conditions.

The visual stimulation structure used in the forward/reverse intermittent eye movement is black (R=0, G=0, B=0) for the background screen, a cross shape for the FIXATION stimulation, and green for the CUE stimulation (R=0, G=). 255, B=0), a square with a face color of red (R=255, G=0, B=0), and a TARGET stimulus with a face color of white (R=255, G=255, B=255). It can be composed of a square and a square structure with a white (R=255, G=255, B=255) border line color along with this figure.

The size of the visual stimulus used in the forward/reverse intermittent eye movement is 1920 x 1080 px in length, FIXATION stimulus 62 px (1.5°), CUE stimulus 62 px (1.5°), TARGET stimulus 41 px (1°). ) And 82px (2°).

The position of the visual stimulus used in the forward/reverse intermittent eye movement is such that the FIXATION stimulus and the CUE stimulus are located at the center of the background screen (960, 540), and the TARGET stimulus is located at a distance of 418px (10°) from the center of the background screen. can do.

As shown in FIG. 3, the presentation condition of the visual stimulation used in the forward/reverse intermittent eye movement of the eyeball can be performed randomly in a 2:1 ratio of the forward intermittent eye movement and the reverse intermittent eye movement.

When visual stimulation is presented, TARGET stimulation is presented at random for each trial, and the default number of trials can be performed with 60 forward intermittent eye movements and 30 reverse intermittent eye movements for a total of 90 times.

The order of presentation of visual stimuli used in the forward/reverse intermittent eye movement can be presented in the order of FIXATION stimulation → CUE stimulation → GAP stimulation → TARGET stimulation at one time.

In addition, the presentation time of the visual stimulation used in the forward/reverse intermittent eye movement can be presented for a time of 500msec for FIXATION stimulation, 800msec for CUE stimulation, 200msec for GAP stimulation, and 1500msec for TARGET stimulation when administered once.

In interpreting the results of intermittent eye movement, first, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may set forward/reverse intermittent eye movement tasks (410). Step 410 is to determine the visual stimulation to be presented to the test subject, through the forward/reverse intermittent eye movement task, the visual stimulation of FIX, CUE, GAP, and TARGET may be presented.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may pre-process bio-signals related to eye movement for visual stimulation (420). Step 420 may be a process of acquiring and pre-processing an eye movement bio-signal of the test subject while performing the intermittent eye movement task. In addition, in this step 420, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may quantitatively (objective) analyze the eye movement direction, reaction time, and pupil size of the test subject to the visual stimulus.

By repeating the above-described step 420, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may obtain a change in an incorrect answer rate, a response delay time, and a pupil size of the eye movement.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine whether an incorrect answer rate and a response delay time of eye movement exceed a threshold value (430). If the incorrect answer rate and the response delay time exceed the threshold value (in the'Yes' direction of step 430), the eye movement-based degenerative cognitive decline evaluation device 100 can determine the cognitive decline for the test subject. There is (432).

Steps

430 and 432 analyze the bio-signal of eye movement of the test subject, compare the rate of incorrect answer and the response delay time of the eye movement to the visual stimulus of the intermittent eye movement task with a threshold value, and the comparison result exceeds the threshold value. In this case, it may be a process of determining that cognitive function is deteriorated.

On the other hand, if the incorrect answer rate and the response delay time do not exceed the threshold value (in the'No' direction of step 430), the eye movement-based degenerative cognitive decline evaluation device 100 is It may be determined again whether it exceeds (440). If the change in pupil size exceeds the threshold value (in the'Yes' direction of step 440), the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine the subject as a risk group for cognitive decline. (442), Steps (440, 442), if the incorrect answer rate and response delay time of eye movement are within the threshold value, the change in pupil size is compared with the threshold value, and if the result of the comparison exceeds the threshold value, cognitive function decline It may be a process of judging as a risk group.

If the change in pupil size does not exceed the threshold value (in the'No' direction in step 440), the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine the subject's normal aging group (450). Step 450 may be a process of determining the test subject as a normal group when the change in the incorrect answer rate, response delay time, and pupil size of the eye movement is within a threshold value.

Hereinafter, in FIG. 5, a work flow of the apparatus 100 for evaluating degenerative cognitive decline based on eye movement according to embodiments of the present invention will be described in detail.

The method for evaluating degenerative cognitive decline based on eye movement according to the present embodiment may be performed by the apparatus 100 for evaluating degenerative cognitive decline based on eye movement.

First, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement analyzes the forward and reverse intermittent eye movements of the eyeball tracking the moving target (510). Step 510 may be a process of analyzing that the target exposed to the test subject moves at a certain speed in a designated section, and thus the test subject moves the eyeball to follow the target.

The forward intermittent eye movement of the eyeball is a movement obtained by allowing the subject to look at the target in the same direction as the moving direction of the target, and can be used as an index to test the test subject's simple reaction ability.

On the other hand, the reverse intermittent eye movement of the eyeball is a movement obtained by allowing the subject to look at the target in the direction opposite to the direction of movement of the target, and is an index that measures direction error and saccade latency. It is utilized, allowing the subject's cognitive information processing ability to be evaluated.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement measures an incorrect answer rate regarding the degree to which the movement of the eyeball deviates from the movement path of the target through the analysis (520). Step 520 may be a process of measuring the difference between the tracking path according to the forward/reverse intermittent eye movement of the eye and the actual movement path of the target by converting it as a ratio.

For example, in tracking a target moving 20 reciprocating times in a predetermined section with a task combined with a forward/reverse ratio of 3:1, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement is 15 times forward/reverse. When the number of deviations from the movement of the eyeball and the target's movement path is '2' during intermittent eye movement, the wrong answer rate is '13.3%', and during 5 reverse intermittent eye movements, the movement of the eyeball and the target When the number of deviations from the movement path of is '1', the incorrect answer rate can be measured as '20.0%', respectively, and movement of the eyeball and deviation from the movement path of the target during intermittent eye movement in the entire forward/reverse direction The number of times becomes '3', so it can be measured with a '15.0%' incorrect answer rate.

In the measurement of the wrong answer rate, the apparatus 100 for evaluating degenerative cognitive function based on eye movement may correct the wrong answer rate by assigning a predetermined weight according to the forward/reverse intermittent eye movement.

In the above example, under the assumption that the incorrect answer rate for the reverse intermittent eye movement is more important to the evaluation of cognitive decline than the incorrect answer rate for the forward intermittent eye movement, the apparatus for evaluating degenerative cognitive function based on eye movement (100) Can correct and measure the incorrect answer rate ((0.133+(0.2*1.1))/(1+1.1)*100=16.8%) by adding a weight of 1.1 to the wrong answer rate for the reverse intermittent eye movement.

In other words, when the wrong answer rate of the forward intermittent eye movement is'E _P ', the wrong answer rate of the reverse intermittent movement is'E _A ', and the weight of the wrong answer rate is'W _E ', eye movement-based degeneration The cognitive decline evaluation apparatus 100 may correct and measure an incorrect answer rate through the _{conversion formula'(E P} +E _A *W _E )/(1 +W _{E) *100'.}

Subsequently, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement measures a response delay time required for the eyeball to track the target in a predetermined section in which the target moves (530 ). Step 530 may be a process of measuring a delay time required for tracking the target with the eyeball in response to the target starting to move in a predetermined section, as the response delay time.

For example, in tracking a target moving 20 times in a fixed section with a task combined with a forward/reverse ratio of 3:1, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement is 15 times forward/reverse. It can be measured as the average delay time of the eyeball during intermittent eye movement '0.4 seconds' and the average delay time of the eyeball at 5 times of reverse intermittent eye movement '0.5 seconds'. During eye movement, the average delay time of the eyeball '0.42 seconds' can be measured as the response delay time.

Also in the measurement of the response delay time, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may correct the response delay time by assigning a predetermined weight according to the forward/reverse intermittent eye movement.

In the above example, under the assumption that the average delay time for the reverse intermittent eye movement is more important to the evaluation of cognitive decline than the average delay time for the forward intermittent eye movement, the apparatus for evaluating degenerative cognitive function based on eye movement ( 100) can correct and measure the response delay time ((0.4+(0.5*1.1))/(1+1.1)=0.452) by adding a weight of 1.1 to the average delay time for the reverse intermittent eye movement.

That is, when the response delay time of the forward intermittent eye movement is'L _P ', the response delay time of the reverse intermittent eye movement is'L _A ', and the weight of the response delay time is'W _L ', The apparatus 100 for evaluating degenerative cognitive decline based on eye movement may correct and measure the response delay time through the _{conversion formula'(L P} +L _A *W _L )/(1 + W _{L )'.}

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement, when any one of the wrong answer rate and the response delay time is greater than or equal to a selected threshold, reduces cognitive function for a subject who recognizes an object through the eyeball. It is determined (540). Step 540 compares each of the previously measured incorrect answer rate and response delay time with a threshold value, and if any one of the incorrect answer rate or response delay time as a result of the comparison is greater than or equal to the threshold value, there is an abnormality in the cognitive function of the test subject. It may be a process of judging by.

For example, when the threshold values of the incorrect answer rate and the response delay time are selected as 20% and 0.3 seconds, respectively, the eye movement-based degenerative cognitive decline evaluation device 100 indicates that the previously measured incorrect answer rate of 25% is greater than or equal to the threshold value of 20%. By checking, it is possible to determine the cognitive decline for the subject.

In the selection of the threshold value, the apparatus 100 for evaluating degenerative cognitive function based on eye movement may select the threshold value through computational processing on the incorrect answer rate and response delay time acquired in the normal aging group.

The apparatus 100 for evaluating degenerative cognitive decline based on eye movement calculates the average and standard deviation of the response delay time for each of the reverse intermittent eye movement and the forward intermittent eye movement in a previously selected normal group. And, using the average and the standard deviation, it may be selected as the threshold value to be compared with the response delay time. That is, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement is the average of the response delay time for the intermittent eye movement of the group member in the group from the group whose eye movement is determined to be normal. And standard deviation (SD).

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement calculates the average and standard deviation of the wrong answer rates for the reverse intermittent eye movement in the normal no-go group selected in advance, and the average and the standard deviation By using, it may be selected as the threshold value to be compared with the incorrect answer rate. That is, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement is the response delay time for the reverse intermittent eye movement of the group members within the group from the group whose eye movement is determined to be normal. It can play a role of finding the mean (Mean) and standard deviation (SD) of.

After obtaining the average and the standard deviation, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may select a result of calculating'average + 1.5 * standard deviation' as the threshold value. That is, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may select a value obtained by adding an average to a standard deviation to which a weight of '1.5' is assigned, as a threshold value for an incorrect answer rate and a response delay time.

In another embodiment, when both the incorrect answer rate and the response delay time are less than the threshold value, the eye movement-based degenerative cognitive function decline evaluation apparatus 100 analyzes a change in the size of the pupil in the eyeball. That is, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may further analyze the change in pupil size without determining that the cognitive function is normal even if both the previously measured incorrect answer rate and the response delay time are less than the threshold value. .

Through this, the apparatus 100 for evaluating degenerative cognitive function decline based on eye movement may make the determination of cognitive decline in the test subject more accurate.

In the change in the size of the pupil, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may present a visual stimulus in the field of view of the eyeball. Here, the visual stimulation is a FIXATION stimulation to fix the eyeball, CUE stimulation to distinguish forward and reverse intermittent eye movements, GAP stimulation to control the response effect to the presentation of target stimulation, forward and reverse intermittent eyeballs. It can consist of TARGET stimulation to move the position of the target according to the movement.

The apparatus 100 for evaluating degenerative cognitive decline based on eye movement may present visual stimulation in the order of the FIXATION stimulation, the CUE stimulation, the GAP stimulation, and the TARGET stimulation.

Thereafter, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may analyze a change in the size of the pupil between a time point at which the CUE stimulation is presented and a time point immediately before the GAP stimulation is presented in the field of view. That is, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement checks the pupil at the point where the intermittent eye movement changes from the forward direction to the reverse direction, and the pupil at the point immediately before the eyeball adapts according to the change of direction, and changes. You can analyze the size.

In addition, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement determines a detailed state of the cognitive decline in consideration of the change in the size of the pupil. That is, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement may determine what grade the pupil size change belongs to within a selected range, and determine a specific state for the decrease in cognitive ability of the test subject.

The range is configured to include a plurality of grades, and the apparatus 100 for evaluating degenerative cognitive function decline based on eye movement may determine the detailed state of the cognitive decline according to the grade within the range to which the change in the size of the pupil belongs, ' It can be determined as one of the initial stage of cognitive decline,'memory cognitive decline stage', and'high-risk stage of cognitive decline'.

That is, the apparatus 100 for evaluating degenerative cognitive decline based on eye movement can identify a specific grade within a range corresponding to a change in the size of the pupil, and recognize the state of cognitive decline corresponding to the identified grade in detail. To be.

For example, if the change in pupil size identified between the time point at which the CUE stimulation is presented and the time point immediately before the GAP stimulation is presented in the field of view falls within the second grade within the range, evaluation of degenerative cognitive decline based on eye movement The device 100 may determine the'memory cognitive function deterioration step' corresponding to the second grade as a detailed state of the test subject.

According to an embodiment of the present invention, in the forward/reverse intermittent eye movement, an algorithm for inducing and evaluating the activity of high cognitive function is designed, and the movement direction of the eyeball, the wrong answer rate, the response delay time, and the size of the pupil. By using the change as an objective evaluation variable, it is possible to provide a method and apparatus for evaluating degenerative cognitive decline based on eye movement, which evaluates cognitive decline.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and usable to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. -A hardware device specially configured to store and execute program instructions such as magneto-optical media, and ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operation of the embodiment, and vice versa.

The software may include a computer program, code, instructions, or a combination of one or more of these, configuring the processing unit to operate as desired or processed independently or collectively. You can command the device. Software and/or data may be interpreted by a processing device or, to provide instructions or data to a processing device, of any type of machine, component, physical device, virtual equipment, computer storage medium or device. , Or may be permanently or temporarily embodyed in a transmitted signal wave. The software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

As described above, although the embodiments have been described by the limited drawings, a person of ordinary skill in the art can apply various technical modifications and variations based on the above. For example, the described techniques are performed in a different order from the described method, and/or components such as systems, structures, devices, circuits, etc. described are combined or combined in a form different from the described method, or other components Alternatively, even if substituted or substituted by an equivalent, an appropriate result can be achieved.

Therefore, other implementations, other embodiments, and claims and equivalents fall within the scope of the following claims.

Claims

Analyzing the forward and reverse intermittent eye movements of the eyeball tracking the moving target;

Measuring an incorrect answer rate regarding a degree of deviation of the movement of the eyeball from the movement path of the target through the analysis;

Measuring a response delay time required for the eyeball to track the target in a predetermined section in which the target moves through the analysis; And

If any one of the incorrect answer rate and the response delay time is greater than or equal to a selected threshold, determining a cognitive decline for a subject who recognizes an object through the eyeball

Eye movement-based degenerative cognitive decline evaluation method comprising a.
The method of claim 1,

Calculating an average and standard deviation of response delay times for each of the reverse intermittent eye movements and the forward intermittent eye movements in a pre-selected normal nodule group; And

Selecting the threshold value to be compared with the response delay time by using the average and the standard deviation

Eye movement-based degenerative cognitive decline evaluation method further comprising a.
The method of claim 1,

Calculating the average and standard deviation of the wrong answer rates for the reverse intermittent eye movement in the normal no-go group selected in advance; And

Selecting the threshold value to be compared with the incorrect answer rate using the average and the standard deviation

Eye movement-based degenerative cognitive decline evaluation method further comprising a.
The method according to claim 2 or 3,

The step of selecting as the threshold value,

Selecting the result of calculating'average + 1.5 * standard deviation' as the threshold value

Eye movement-based degenerative cognitive decline evaluation method comprising a.
The method of claim 1,

When both the incorrect answer rate and the response delay time are less than the threshold value,

Analyzing a change in the size of the pupil in the eyeball; And

Determining a detailed state of the cognitive decline in consideration of the change in the size of the pupil

Eye movement-based degenerative cognitive decline evaluation method comprising a.
The method of claim 5,

Analyzing the change in the size of the pupil in the eye,

Presenting visual stimulation in the field of view of the eyeball-The visual stimulation is a FIXATION stimulation to fix the eyeball's gaze, CUE stimulation to distinguish between forward and reverse intermittent eye movements, and response effects to target stimulation control GAP stimulation for the target, TARGET stimulation to move the position of the target according to the forward and reverse intermittent eye movements are presented in the order of -; And

Analyzing the change in the size of the pupil between the time point at which the CUE stimulation is presented and the time point immediately before the GAP stimulation is presented in the field of view

Eye movement-based degenerative cognitive decline evaluation method comprising a.
The method of claim 5,

The step of determining the detailed state of the cognitive decline,

The change in the size of the pupil is compared with the selected range, and according to the grade within the range to which the change in the size of the pupil belongs, the detailed state of the cognitive decline is described as'initial stage of cognitive decline','memory cognitive decline Step', and the step of judging as one of the'high risk of cognitive decline'

Eye movement-based degenerative cognitive decline evaluation method comprising a.
An analysis unit for analyzing the forward and reverse intermittent eye movements of the eyeball that tracks the moving target;

Through the analysis, the rate of incorrect answer regarding the degree to which the movement of the eyeball deviates from the movement path of the target is measured, and in a predetermined section in which the target moves, the response required for the eyeball to track the target A measuring unit for measuring a delay time; And

When any one of the wrong answer rate and the response delay time is greater than or equal to a selected threshold, a determination unit that determines a cognitive decline for a subject who recognizes an object through the eyeball

Eye movement-based degenerative cognitive decline evaluation device comprising a.
The method of claim 8,

Calculate the average and standard deviation of the response delay time for each of the reverse intermittent eye movement and the forward intermittent eye movement in the preselected normal no-go group, and using the average and the standard deviation, the response A processing unit that selects the threshold value to be compared with the delay time

Eye movement-based degenerative cognitive decline evaluation device further comprising a.
The method of claim 8,

Calculate the average and standard deviation of the wrong answer rate for the reverse intermittent eye movement in the normal no-go group selected in advance, and select the threshold value to be compared with the incorrect answer rate using the average and the standard deviation. Processing unit

Eye movement-based degenerative cognitive decline evaluation device further comprising a.
The method of claim 9 or 10,

The processing unit,

The result of calculating'mean + 1.5 * standard deviation' is selected as the threshold value.

A device for evaluating degenerative cognitive decline based on eye movement.
The method of claim 9,

When both the incorrect answer rate and the response delay time are less than the threshold value,

The analysis unit,

Analyzing the change in the size of the pupil in the eye,

The determination unit,

Considering the change in the size of the pupil, to determine the detailed state of the cognitive decline

A device for evaluating degenerative cognitive decline based on eye movement.
The method of claim 12,

The analysis unit,

Visual stimulation is presented in the field of view of the eyeball-The visual stimulation is a FIXATION stimulation to fix the eyeball's gaze, CUE stimulation to distinguish between forward and reverse intermittent eye movements, and control of the response effect to the presentation of target stimulation. GAP stimulation for forward and reverse intermittent eye movements are presented in the order of TARGET stimulation to move the target position-,

Analyzing the change in the size of the pupil between the time point at which the CUE stimulation is presented and the time point just before the GAP stimulation is presented in the field of view

A device for evaluating degenerative cognitive decline based on eye movement.
The method of claim 12,

The determination unit,

The change in the size of the pupil is compared with the selected range, and the detailed state of the cognitive decline is determined according to the grade within the range to which the change in the size of the pupil belongs,'initial stage of cognitive decline','memory cognitive decline. Stage', and'high-risk stage of cognitive decline'

Device for evaluating degenerative cognitive decline based on eye movement