Method for realizing memory ability evaluation based on digital memory

Abstract

The invention provides a method for realizing memory ability evaluation based on digital memory for a computer device. The method comprises the following steps: displaying a digital memory interface through a display screen; the testee memorizes the number marked on each graph within the specified memory duration until the countdown is finished, and then automatically enters a memory ability test interface; when the testee is subjected to a memory ability test, the testee sequentially clicks the corresponding figures by using a mouse according to a sequence from large to small or from small to large of the figures until all the figures are knocked out at a correct place; calculating an evaluation index of the subject by using the eye movement track and the mouse click action of the subject; and evaluating the memory ability of the subject according to the evaluation index. According to the invention, a digital memory assessment normal form is designed to assess the memory ability of the subject, the interference of education background and image content is reduced to the greatest extent, the test result has the time resolution accurate to millisecond, and the subject with tiny memory difference can be accurately distinguished.

Description

Technical Field

[0001] The present invention relates to the technical field of neuropsychology, and in particular to a method for implementing memory ability assessment based on digital recall. Background Art

[0002] Memory is one of the most important and complex physiological functions of the human brain. Memory is defined as the ability to temporarily and actively retain information in the brain for a specific purpose. This information is involved in various cognitive activities, from allocating attention to decision-making. Numerous studies have shown that memory declines with age, leading researchers to use memory as a neurobehavioral marker of brain aging.

[0003] Currently, the most commonly used method for testing memory ability in clinical settings is the neuropsychological scale questionnaire test, including the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog), the Wechsler Adult Intelligence Scale (WAIS-RC), etc. These scales have been used to screen for mild cognitive impairment (MCI) and early Alzheimer's disease (AD) in clinical settings. These scales assess the subject's cognitive function from multiple dimensions (memory, executive function, language, visual-spatial function, information processing, etc.). The test process for memory function is as follows: the subject is asked to observe or listen to several numbers or common words in life. After a few minutes, the subject is asked to recall them accurately, and the doctor scores the subject based on the accuracy of the recall. For example, the MMSE and MoCA tests utilize three words, with one point awarded for each correct answer. However, the scoring criteria for the MMSE and MoCA tests are too simple. In a test with a total score of 30 points, the score of only three words cannot distinguish between individuals with slightly different memory abilities. Therefore, a "ceiling effect" (for groups with higher education levels) or a "floor effect" (for groups with lower education levels) is prone to occur, resulting in false negatives or false positives. In addition, diagnostic results based on scale questionnaires are easily affected by many external factors and cannot truly reflect the subject's condition, making it difficult to identify MCI patients with symptoms of premature memory loss.

[0004] Another experimental paradigm for assessing memory is the N-back test. The N-back test assesses memory ability as follows: Subjects are asked to memorize a series of visual stimuli, including numbers, text (letters, words), and images (photos, paintings, abstract patterns). When presented with a visual stimulus, subjects are asked to answer whether the current stimulus is identical to the N previous stimuli, i.e., a match. When N is 1, it refers to the comparison between the current stimulus and the previous one. N can be 1, 2, ..., or 4. The stimulus load can be single or multiple (i.e., multiple visual stimuli can be presented simultaneously). Visual stimuli can be letter-matching, position-matching, or image-matching. Stimuli can be either visual or verbal. The N-back test paradigm is simple, and cognitive assessment relies on response accuracy and test completion time. However, N-back test results cannot be subjected to high-precision quantitative analysis or in-depth data mining. Therefore, the N-back test has significant limitations in assessing memory in clinical diagnosis and basic brain research.

[0005] Therefore, we urgently need to develop a new method for evaluating memory ability to address the defects of the above-mentioned memory ability evaluation methods in the prior art. Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0007] Therefore, the object of the present invention is to provide a method for evaluating memory ability based on digital recall.

[0008] In order to achieve the above-mentioned purpose, the technical solution of the present invention provides a method for implementing memory ability assessment based on digital recall, which is used for a computer device, and the computer device includes: a mouse, a display screen, an eye tracker, a jaw rest, a memory, a processor and a computer program stored in the memory and executable on the processor; wherein the mouse is used to control the movement of a cursor on the display screen, the display screen is used to display the test content corresponding to the method for memory ability assessment, the eye tracker is used to record the eye movement trajectory of the subject when responding to the corresponding test content, the jaw rest is used to stabilize the subject's head, and the processor is used to implement the method for memory ability assessment when executing the computer program; the method for memory ability assessment includes: step S1: after receiving an instruction to start the test, a digital memory interface is displayed on the display screen; wherein N randomly distributed graphics are displayed on the digital memory interface, and the shapes of the graphics are arbitrary, and the shapes of the graphics are the same or different; each graphic is marked with a number, and the numbers marked on each graphic are different; each number is a positive integer greater than 1; there is a a timer for countdown, indicating the specified memory time; requiring the subject to memorize the number marked on each graphic within the specified memory time until the countdown ends; after the memory ends, the number marked on each graphic disappears, and the position of each graphic remains unchanged; step S2: after the countdown displayed on the digital memory interface ends, the subject is reminded to enter a rest period of t seconds through the display screen; after the rest period ends, a memory ability test interface is automatically displayed through the display screen; when the subject performs a memory ability test through the memory ability test interface, the subject uses the mouse to click on the corresponding graphics in order from large to small or from small to large according to the number on each memorized graphic, until the subject correctly clicks out all the numbers with the mouse; and when the subject performs the memory ability test, the eye tracker records the subject's eye movement trajectory in real time; t is a natural number greater than 0; step S3: using the subject's eye movement trajectory recorded by the eye tracker and the mouse clicking action to calculate the subject's evaluation index; step S4: according to the subject's evaluation index, an evaluation result of the subject's memory ability is obtained.

[0009] Preferably, when the subject performs a memory ability test through the memory ability test interface, if the subject clicks the graphics in the correct order, the numbers on the graphics corresponding to the correct clicks reappear; when the subject performs a memory ability test through the memory ability test interface, if the subject clicks the graphics in the wrong order, the graphics corresponding to the wrong clicks will turn into a specific color within a preset time, and the computer device will emit an alarm sound through the alarm unit; after the computer device emits an alarm sound through the alarm unit, the graphics corresponding to the wrong clicks will be restored from the specific color to the original color, so that the subject can continue to click on the graphics corresponding to the wrong clicks until the test is completed.

[0010] Preferably, the evaluation index of the subject includes one of the following or a combination thereof: recall accuracy, total completion time, segmentation time, path ratio, first click error sequence number, memory capacity, and digital recall sequence deviation ρ;

[0011] The recall accuracy rate is the ratio of the number of correct mouse clicks by the subject during the memory test to the total number of mouse clicks by the subject during the memory test.

[0012] The calculation formula for recall accuracy ACC is:

[0013] ACC=N / n (1)

[0014] In formula (1), N is the number of correct clicks of the mouse during the memory test; n is the total number of mouse clicks during the memory test;

[0015] The total completion time is: the time it takes for the subject to correctly click the last number from the time the subject clicks the first number with the mouse;

[0016] The segment duration is: the time it takes for the subject to correctly click the i-th number to correctly click the (i+1)-th number; the value range of i is greater than or equal to 1 and less than or equal to (N-1);

[0017] The calculation formula for the segment duration is:

[0018] ΔT[(i+1)-(i)]=T i+1 -T i (2)

[0019] In formula (2), T i+1 is the time when the subject clicks the (i+1)th number; T i is the time when the subject clicks the i-th number;

[0020] The path ratio is: the ratio of the length of the eye movement trajectory of the subject in the process of searching for the (i+1)th number after correctly clicking the i-th number to the straight-line distance between the i-th number and the (i+1)th number on the memory ability test interface;

[0021] The calculation formula of the path ratio is:

[0022] R[(i+1)-(i)]=S (i+1)-(i) / D (i+1)-(i) (3)

[0023] In formula (3), S (i+1)-(i) D represents the length of the eye movement trajectory when the subject searches for the (i+1)th number after correctly clicking the i-th number; (i+1)-(i) Represents the straight-line distance between the i-th number and the (i+1)-th number on the memory ability test interface;

[0024] The first click error serial number is: the serial number i corresponding to the number clicked incorrectly when the subject makes the click error for the first time;

[0025] The calculation formula of the memory capacity is:

[0026] Memory capacity = N × (ACC – 0.5) / 0.5 (4)

[0027] In formula (4), N is the total number of numbers marked on all graphics during the subject's memory ability test; ACC is the recall accuracy rate;

[0028] The number recall sequence deviation ρ is the degree of deviation between the order in which the subject actually clicks the numbers and the prescribed order when taking the memory ability test.

[0029] Preferably, the calculation process of the digital recall sequence deviation ρ specifically includes: marking the sequence corresponding to the click sequence specified when the subject takes the memory ability test as X = [x1, x2, ..., x N ]; where x i is the i-th number in the sequence corresponding to the specified click order; wherein N is the total number of numbers corresponding to the specified click order; the sequence corresponding to the order in which the subject actually clicks the numbers when taking the memory ability test is marked as Y = [y1, y2, ..., y n ]; where y jis the jth number in the sequence corresponding to the order of the actual clicked numbers; wherein n is the total number of numbers corresponding to the order of the actual clicked numbers; according to the sequence corresponding to the specified click order and the sequence corresponding to the order of the actual clicked numbers, an N×n dimension distance matrix D is constructed; wherein the element d(i,j) of the distance matrix D is the number x i to the number y j The absolute value of the distance between them; a cumulative distance matrix C is constructed from the distance matrix D; wherein the element c(i,j) of the cumulative distance matrix C is the element d(i,j) of the distance matrix D plus the minimum value of the elements {c(i-1,j),c(i,j-1),c(i-1,j-1)} in the cumulative distance matrix C; the minimum value of the elements {c(i-1,j),c(i,j-1),c(i-1,j-1)} in the cumulative distance matrix C is the number x i With the number y j The minimum cumulative distance between two points; the value of the element c(N,n) in the cumulative distance matrix C is the degree of deviation between the order in which the subject actually clicks the numbers when taking the memory ability test and the prescribed click order; when the order in which the subject actually clicks the numbers when taking the memory ability test is completely consistent with the prescribed click order, the number recall order deviation ρ is zero.

[0030] Beneficial effects of the present invention:

[0031] (1) The method for evaluating memory ability based on digital recall for a computer device provided by the present invention is to use eye tracking technology to record the non-subjective conscious response of the subject while presenting visual stimuli. Eye tracking technology is a new technology that can measure eye movements when the subject is objectively reading, scanning and saccade. In recent years, it has been used for cognitive function assessment, such as trajectory testing, saccades and antisaccades, emotion recognition and cognitive assessment. Eye tracking technology has unique technical advantages. First, the eye movements recorded by eye tracking technology are autonomous reflections of brain perceptual activities (visual and / or auditory), which are not controlled by human consciousness and can truly reflect the cognitive activities of the subject. Second, eye tracking technology can continuously monitor and record eye movements, providing dynamic information of cognitive performance in a real-time framework, rather than static final results, such as PET, MRI or neuropsychological scale questionnaire test results. Third, the eye movement trajectory projected onto the monitor using eye tracking technology has higher spatial resolution (several pixels) and temporal resolution (milliseconds), which can record rapid brain activities. These digital testing methods are more accurate, convenient, and subject-friendly than memory ability assessments based on paper-and-pencil neuropsychological scales.

[0032] (2) The present invention provides a method for evaluating memory ability based on digit recall for a computer device. We designed a digit recall assessment paradigm to evaluate the memory ability of participants of different ages or cognitive levels. Unlike other experiments that use images, words, or letter strings as stimuli, the present invention uses only numbers, minimizing the influence of educational background (e.g., familiarity with letters or words) and image content (e.g., visual disorders, colors, religious beliefs, and personal biases).

[0033] (3) Compared with existing research and testing methods, the method for evaluating memory ability based on digital recall for computer devices provided by the present invention has two unique features. First, in addition to the two evaluation indicators of recall accuracy and total completion time, we also obtained information such as path ratio, memory capacity, serial number of first click error, segmentation time, and digital recall sequence deviation ρ, which enables us to understand the memory performance of the subjects more comprehensively. For example, even if different participants make the same number of wrong clicks, our method can show how they made the wrong clicks, which number was wrongly clicked, and how much time they spent before making the wrong click. Second, our method is more accurate than previously published data. The test results of the evaluation indicators obtained by this method have a time resolution accurate to milliseconds, which can accurately distinguish subjects with smaller memory differences.

[0034] Additional aspects and advantages of the invention will become apparent from the description which follows, or may be learned by practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic block diagram illustrating the working principle of a computer device according to an embodiment of the present invention;

[0036] Figure 2 A schematic flow chart showing a method for implementing memory ability assessment based on digital recall in a computer device according to an embodiment of the present invention;

[0037] Figure 3 A schematic diagram illustrating a digital memory interface according to an embodiment of the present invention is shown;

[0038] Figure 4 A schematic diagram showing an interface at the end of a countdown according to an embodiment of the present invention;

[0039] Figure 5 A schematic diagram showing a memory ability test interface after a subject correctly clicks numbers 1 and 2 according to an embodiment of the present invention;

[0040] Figure 6A schematic diagram illustrating a memory ability test interface according to an embodiment of the present invention after a subject correctly clicks numbers 1 and 2 but fails to correctly click number 3 and mistakenly clicks other numbers;

[0041] Figure 7 A schematic diagram showing statistical results of recall accuracy rates of subjects corresponding to three age groups obtained according to an embodiment of the present invention;

[0042] Figure 8 A bar chart showing the recall accuracy of subjects corresponding to three age groups obtained according to an embodiment of the present invention;

[0043] Figure 9 A schematic diagram showing the sequence distribution laws corresponding to the first, second, third, and fourth recall errors of the youth group subjects obtained according to one embodiment of the present invention;

[0044] Figure 10 A schematic diagram showing the sequence distribution laws corresponding to the first, second, third, and fourth recall errors of middle-aged subjects obtained according to one embodiment of the present invention;

[0045] Figure 11 A schematic diagram showing the sequence distribution laws corresponding to the first, second, third, fourth, fifth, and sixth recall errors of elderly subjects obtained according to one embodiment of the present invention;

[0046] Figure 12 A schematic diagram showing the total completion time corresponding to subjects in three age groups obtained according to an embodiment of the present invention;

[0047] Figure 13 A schematic diagram showing the segment durations corresponding to subjects in three age groups obtained according to an embodiment of the present invention;

[0048] Figure 14 A schematic diagram showing the path ratios corresponding to subjects in three age groups obtained according to an embodiment of the present invention is shown;

[0049] Figure 15 A schematic diagram showing the digit recall sequence deviations ρ corresponding to subjects in three age groups obtained according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0050] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, Figures 1 to 15 As shown, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0051] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0052] Figure 1 A schematic block diagram showing the working principle of a computer device according to an embodiment of the present invention. Figure 2 FIG1 is a schematic flow chart showing a method for implementing memory ability assessment based on digital recall for a computer device according to an embodiment of the present invention. Figure 1 and Figure 2 As shown, the method for implementing memory ability assessment based on digital recall is used in a computer device, which includes: a mouse, a display screen, an eye tracker, a jaw rest, a memory, a processor, and a computer program stored in the memory and runnable on the processor; wherein the mouse is used to control the movement of the cursor on the display screen, the display screen is used to display the test content corresponding to the method for memory ability assessment, the eye tracker is used to record the eye movement trajectory of the subject when responding to the corresponding test content, and the jaw rest is used to stabilize the subject's head to ensure that the subject's head does not swing significantly during the assessment process, thereby achieving the purpose of ensuring the acquisition of high-quality eye movement data. The processor is used to implement the method for memory ability assessment when executing the computer program; the method for memory ability assessment includes:

[0053] Step S10: After receiving the instruction to start the test, a digital memory interface is displayed on the display screen; wherein the digital memory interface displays N randomly distributed graphics, the shapes of the graphics are arbitrary, and the shapes of the graphics are the same or different; each graphic is marked with a number, and the numbers marked on each graphic are different; each number is a positive integer greater than 1; the digital memory interface has a countdown timer, indicating the specified memory duration; the subject is required to memorize the number marked on each graphic within the specified memory duration until the countdown ends; after the memory ends, the number marked on each graphic disappears, and the position of each graphic remains unchanged;

[0054] Step S20: After the countdown displayed on the digital memory interface ends, the display screen reminds the subject to enter a rest period of t seconds; after the rest period ends, the display screen automatically displays a memory ability test interface; when the subject performs a memory ability test on the memory ability test interface, the subject uses the mouse to click on the corresponding graphics in order from large to small or from small to large according to the numbers on each graphic to be memorized, until the subject correctly clicks on all the numbers with the mouse; and when the subject performs the memory ability test, the eye tracker records the subject's eye movement trajectory in real time; t is a natural number greater than 0;

[0055] Step S30: Calculating the subject's evaluation index using the subject's eye movement trajectory and mouse click actions recorded by the eye tracker;

[0056] Step S40: Obtaining an evaluation result of the subject's memory ability based on the subject's evaluation index.

[0057] In this embodiment, the present invention provides a method for evaluating memory ability based on digit recall in a computer device. This method employs a digit recall assessment paradigm to assess the memory abilities of participants of different age groups. Unlike other experiments that use images, words, or letter strings as stimuli, the present invention uses only digits, minimizing the influence of educational background (e.g., familiarity with letters or words) and image content (e.g., visual impairments, colors, religious beliefs, and personal biases).

[0058] In this embodiment, compared with the existing research test methods, the method for implementing memory ability assessment based on digital recall for a computer device provided by the present invention has two unique features. First, in addition to the two evaluation indicators of recall accuracy and total completion time, we also obtained information such as path ratio, memory capacity, serial number of first click error, segmentation time, and digital recall sequence deviation ρ, which enables us to have a more comprehensive understanding of the subject's memory performance. For example, even if different participants make the same number of wrong clicks, our method can show how they made the wrong clicks, which number was wrongly clicked, and how much time was spent before they made the wrong click. Secondly, our method is more accurate than previously published data. The test results of the evaluation indicators obtained by this method have a time resolution accurate to milliseconds, which can accurately distinguish subjects with smaller memory differences.

[0059] In one embodiment of the present invention, when a subject performs a memory ability test through a memory ability test interface, if the subject clicks on graphics in the correct order, the numbers on the graphics corresponding to the correct clicks will reappear; when a subject performs a memory ability test through a memory ability test interface, if the subject clicks on graphics in the wrong order, the graphics corresponding to the wrong clicks will turn into a specific color within a preset time, and the computer device will emit an alarm sound through the alarm unit; after the computer device emits an alarm sound through the alarm unit, the graphics corresponding to the wrong clicks will be restored from the specific color to the original color, so that the subject can continue to click on the graphics corresponding to the wrong clicks until the test is completed.

[0060] In one embodiment of the present invention, the evaluation index of the subject includes one of the following or a combination thereof: recall accuracy, total completion time, segmentation time, path ratio, first click error sequence number, memory capacity, and digital recall sequence deviation ρ;

[0061] The recall accuracy rate is the ratio of the number of correct mouse clicks by the subject during the memory test to the total number of mouse clicks by the subject during the memory test.

[0062] The calculation formula for recall accuracy ACC is:

[0063] ACC=N / n (1)

[0064] In formula (1), N is the number of correct clicks of the mouse during the memory test; n is the total number of mouse clicks during the memory test;

[0065] The total completion time is: the time it takes for the subject to correctly click the last number from the time the subject clicks the first number with the mouse;

[0066] The segment duration is: the time it takes for the subject to correctly click the i-th number to correctly click the (i+1)-th number; the value range of i is greater than or equal to 1 and less than or equal to (N-1);

[0067] The calculation formula for the segment duration is:

[0068] ΔT[(i+1)-(i)]=T i+1 -T i (2)

[0069] In formula (2), T i+1 is the time when the subject clicks the (i+1)th number; T i is the time when the subject clicks the i-th number;

[0070] The path ratio is: the ratio of the length of the eye movement trajectory of the subject in the process of searching for the (i+1)th number after correctly clicking the i-th number to the straight-line distance between the i-th number and the (i+1)th number on the memory ability test interface;

[0071] The calculation formula of the path ratio is:

[0072] R[(i+1)-(i)]=S (i+1)-(i) / D (i+1)-(i) (3)

[0073] In formula (3), S (i+1)-(i) D represents the length of the eye movement trajectory when the subject searches for the (i+1)th number after correctly clicking the i-th number; (i+1)-(i) Represents the straight-line distance between the i-th number and the (i+1)-th number on the memory ability test interface;

[0074] The first click error serial number is: the serial number i corresponding to the number clicked incorrectly when the subject makes the click error for the first time;

[0075] The calculation formula of the memory capacity is:

[0076] Memory capacity = N × (ACC – 0.5) / 0.5 (4)

[0077] In formula (4), N is the total number of numbers marked on all graphics during the subject's memory ability test; ACC is the recall accuracy rate;

[0078] The number recall sequence deviation ρ is the degree of deviation between the order in which the subject actually clicks the numbers and the prescribed order when taking the memory ability test.

[0079] In one embodiment of the present invention, the calculation process of the digital recall sequence deviation ρ specifically includes: marking the sequence corresponding to the click sequence specified when the subject takes the memory ability test as X = [x1, x2, ..., x N ]; where x i is the i-th number in the sequence corresponding to the specified click order; wherein N is the total number of numbers corresponding to the specified click order; the sequence corresponding to the order in which the subject actually clicks the numbers when taking the memory ability test is marked as Y = [y1, y2, ..., y n ]; where y j is the jth number in the sequence corresponding to the order of the actual clicked numbers; wherein n is the total number of numbers corresponding to the order of the actual clicked numbers; according to the sequence corresponding to the specified click order and the sequence corresponding to the order of the actual clicked numbers, an N×n dimension distance matrix D is constructed; wherein the element d(i,j) of the distance matrix D is the number x i to the number y j The absolute value of the distance between them; a cumulative distance matrix C is constructed from the distance matrix D; wherein the element c(i,j) of the cumulative distance matrix C is the element d(i,j) of the distance matrix D plus the minimum value of the elements {c(i-1,j),c(i,j-1),c(i-1,j-1)} in the cumulative distance matrix C; the minimum value of the elements {c(i-1,j),c(i,j-1),c(i-1,j-1)} in the cumulative distance matrix C is the number x i With the number y jThe minimum cumulative distance between two points; the value of the element c(N,n) in the cumulative distance matrix C is the degree of deviation between the order in which the subject actually clicks the numbers when taking the memory ability test and the prescribed click order; when the order in which the subject actually clicks the numbers when taking the memory ability test is completely consistent with the prescribed click order, the number recall order deviation ρ is zero.

[0080] The technical solution of the present invention will be demonstrated below with a specific embodiment 1.

[0081] Example 1

[0082] Subjects:

[0083] A total of 108 volunteers were recruited for this study. They came from schools, ordinary community residents, and grassroots workers. They were divided into three age groups: those under 45 years old (younger group), those aged 45-60 years old (middle-aged group), and those aged 60 years and older (older group). Information about the participants in each age group is shown in Table 1.

[0084] The inclusion criteria for participants in this study were: (1) normal daily living and social interaction skills; (2) education level of junior high school or above; (3) no major physical illness or eye disease that affects vision (including color blindness); (4) sufficient cognitive and language ability to complete the neuropsychological scale assessment; (5) able to correctly understand the experimental significance of this study and have good compliance; (6) voluntary participation in this study. The exclusion criteria for volunteers participating in this study were: (1) history of mental illness; (2) brain trauma; (3) eye disease that affects vision.

[0085] Table 1 Subject information

[0086]

[0087]

[0088] Ethics Statement:

[0089] This study adhered to the principles of the Declaration of Helsinki and was evaluated and approved by the Research Ethics Committee of China Medical University (No. 202373). All study participants read the study notice and signed the informed consent form before participating in the study. All participants were verbally informed of the overall purpose of the experiment and agreed to participate.

[0090] Statistical analysis:

[0091] The results of this experiment are presented as mean ± standard deviation. Homogeneity of variance and normality of the data were tested using the Shapiro-Wilk and Levene methods. If the samples followed the normal distribution test and homogeneity of variance was tested, comparisons between multiple groups were performed using ANOVA and the Buffoni test. If the data did not follow the normal distribution and homogeneity of variance was tested, comparisons between multiple groups were performed using the Kruskal-Wallis one-way ANOVA test and the Mann-Whitney test with Buffoni correction. Statistical analysis was performed using Origin 2022 software. Differences were considered statistically significant when P < 0.05.

[0092] Experimental design:

[0093] The subjects sat steadily in front of the memory ability test instrument, placed their chin on the chin rest of the instrument, and tried to keep their heads still during the test.

[0094] The method for implementing memory ability assessment based on digital recall by a computer device specifically comprises the following steps:

[0095] (1) After receiving the instruction to start the test, a digital memory interface is displayed on the display screen; wherein the digital memory interface displays N randomly distributed graphics, the shapes of the graphics are arbitrary, and the shapes of the graphics are the same or different; each graphic is marked with a number, and the numbers marked on each graphic are different; each number is a positive integer greater than 1; the digital memory interface has a countdown timer, indicating the specified memory time; the subject is required to remember the number marked on each graphic within the specified memory time until the countdown ends;

[0096] In this specific embodiment, Figure 3 As shown, the graphic is set to a regular circle, the number of regular circles is set to 8, the numbers are 1, 2, 3, ..., 8 respectively, and the countdown time is set to 8 seconds;

[0097] like Figure 4 As shown, after the memory is finished, the number marked on each regular circle disappears, and the position of each regular circle remains unchanged;

[0098] (2) After the countdown displayed on the digital memory interface ends, the display screen reminds the subject to enter a rest period of t seconds; after the rest period ends, the display screen automatically displays the memory ability test interface; when the subject performs the memory ability test through the memory ability test interface, the subject uses the mouse to click on the corresponding regular circles in ascending order according to the numbers on each regular circle in memory, until the subject correctly clicks out all the numbers with the mouse; and when the subject performs the memory ability test, the eye tracker records the subject's eye movement trajectory in real time; t is a natural number greater than 0;

[0099] In this specific embodiment, the order of clicking the numbers is set to be in a positive order from small to large;

[0100] like Figure 5 As shown, after the subject correctly recalled (i.e., clicked) the numbers 1 and 2, the numbers on the regular circles corresponding to the correct clicks (i.e., numbers 1 and 2) reappeared;

[0101] Furthermore, if Figure 6 As shown, after the subject correctly clicks numbers 1 and 2, but fails to click number 3 and mistakenly clicks other numbers, that is, when the subject makes a mistake in the order of clicking the regular circles, the regular circles corresponding to the mistaken clicks will turn red within a preset time;

[0102] (3) Using the eye movement trajectories and mouse clicks recorded by the eye tracker, the subject's evaluation index is calculated;

[0103] (4) Based on the subject's evaluation indicators, obtain the evaluation results of the subject's memory ability.

[0104] Experimental results:

[0105] The test results of the present invention on the subjects of these three different age groups are shown in Table 2.

[0106] Table 2 Test results of Example 1

[0107]

[0108] First, this experiment used the recall accuracy rate to quantitatively measure the memory ability of subjects in different age groups. Figure 7 As shown in the figure, the recall accuracy rates of the young, middle-aged and elderly groups were 90.71%, 78.67% and 59.91% respectively, and there was a significant difference in the click accuracy rates between the two groups (P<10 -8 ). The memory capacities of the three groups of subjects were 6.51, 4.59, and 1.58, respectively. Figure 8 The distribution of recall accuracy of subjects in three age groups (<70%, 70%-90%, 90%<) is shown. Figure 8 As shown, no subject in the elderly group had a recall accuracy higher than 90%, while nearly 60% of the subjects in the young group had a recall accuracy higher than 90%. Figure 9 — Figure 11 The distribution of recall errors among young, middle-aged, and elderly subjects is shown. Figure 9 、 Figure 10 and Figure 11As shown in Figure 2, the median number of first recall errors for the young, middle-aged, and elderly groups was 5, 4, and 3, respectively. The maximum number of recall errors for the young and middle-aged groups in the digit memory experiment was four, while the maximum number of recall errors for the elderly group was six. Figure 11 In terms of the distribution density of recall error points, the distribution range of recall errors in the elderly group was larger than that in the young group ( Figure 9 ) and middle-aged group ( Figure 10 ) is wider. There are significant differences in the location and number of recall errors among subjects of different age groups. The greater the number of recall errors, the earlier the numerical sequence in which the recall errors occurred.

[0109] The total time taken by the three groups of subjects to complete the digital memory experiment was analyzed. Figure 12 The results showed that as age increased, the total time it took for the subjects in the youth, middle-aged and elderly groups to complete the memory test was 962.17ms, 1675.17ms and 3617.50ms respectively, and there was a statistically significant difference between the two groups (P<10 -8 Compared with the young group, the total time taken by the middle-aged and elderly groups increased by 1.74 times and 3.75 times, respectively. Figure 13 is the time it takes for the young, middle-aged, and elderly subjects to recall numbers in the memory test. Figure 13 As shown in the figure, all three curves indicate that the process of recalling numbers is an uneven process. In addition, analysis of the subjects' eye movement characteristics also found that the path ratios of the young, middle-aged and elderly groups in this experiment were 5.4, 11.55 and 13.77 respectively, and there was a statistically significant difference between each two groups (P < 10 -8 Compared with the young group, the path ratios of the middle-aged group and the elderly group increased by 2.1 times and 2.55 times, respectively (e.g. Figure 14 shown).

[0110] Figure 15 is the deviation of the digital recall order when the subjects of the three age groups were tested for memory ability. Figure 15 As shown, the deviation of the digit recall order of the young group of subjects was only 1.715, far lower than that of the middle-aged group (4.389) and the elderly group (11.511). The deviation of the digit recall order of the middle-aged group of subjects was also far lower than that of the elderly group. This shows that the order of the digits recalled by the young group of subjects is very close to the prescribed order of digits, that is, the young group of subjects has very good memory ability.

[0111] in conclusion:

[0112] The method for evaluating memory ability based on digital recall of the present invention can effectively identify the memory ability of a subject based on multiple indicators, and the result is far superior to the evaluation method of the existing neuropsychological scale.

[0113] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for implementing memory ability assessment based on digital recall, for use in a computer device, the computer device comprising: A mouse, a display screen, an eye tracker, a jaw rest, a memory, a processor, and a computer program stored in the memory and executable on the processor; wherein the mouse is used to control the movement of a cursor on the display screen, the display screen is used to display the test content corresponding to the memory ability assessment method, the eye tracker is used to record the eye movement trajectory of the subject when responding to the corresponding test content, the jaw rest is used to stabilize the subject's head, and the processor is used to implement the memory ability assessment method when executing the computer program; the memory ability assessment method includes: Step S1: After receiving a test start instruction, a digital memory interface is displayed on a display screen; wherein the digital memory interface displays N randomly distributed graphics, the shapes of the graphics are arbitrary, and the shapes of the graphics are the same or different; each graphic is marked with a number, and the numbers marked on each graphic are different; each number is a positive integer greater than 1; the digital memory interface has a countdown timer indicating a specified memory duration; the subject is required to memorize the number marked on each graphic within the specified memory duration until the countdown ends; after the memory ends, the number marked on each graphic disappears, and the position of each graphic remains unchanged; Step S2: After the countdown displayed on the digital memory interface ends, the display screen reminds the subject to enter a rest period of t seconds; after the rest period ends, the display screen automatically displays a memory ability test interface; when the subject performs a memory ability test on the memory ability test interface, the subject uses the mouse to click on the corresponding graphics in order from large to small or from small to large according to the numbers on each graphic to be memorized, until the subject correctly clicks out all the numbers with the mouse; and when the subject performs the memory ability test, the eye tracker records the subject's eye movement trajectory in real time; t is a natural number greater than 0; Step S3: calculating the subject's evaluation index using the subject's eye movement trajectory and the mouse click action recorded by the eye tracker; Step S4: Obtaining an evaluation result of the subject's memory ability based on the subject's evaluation indicators.

2. The method for memory ability assessment based on digital recall according to claim 1, characterized in that: When the subject is taking the memory ability test through the memory ability test interface, if the subject clicks the graphics in the correct order, the numbers on the graphics corresponding to the correct clicks will reappear; When the subject is taking a memory ability test through the memory ability test interface, if the subject clicks on the graphics in an incorrect order, the graphics corresponding to the incorrect clicks will turn into a specific color within a preset time, and the computer device will emit an alarm sound through the alarm unit; After the computer device emits an alarm sound through the alarm unit, the graphic corresponding to the click error is restored from the specific color to the original color, so that the subject can continue to click on the graphic corresponding to the click error until the test is completed.

3. The method for memory ability assessment based on digital recall according to claim 1, characterized in that: The evaluation indicators of the subject include one of the following or a combination thereof: recall accuracy, total completion time, segment time, path ratio, first click error sequence number, memory capacity, and digital recall sequence deviation ρ; The recall accuracy rate is the ratio of the number of correct mouse clicks by the subject during the memory test to the total number of mouse clicks by the subject during the memory test. The calculation formula for recall accuracy ACC is: ACC=N / n (1) In formula (1), N is the number of correct clicks of the mouse during the memory test; n is the total number of mouse clicks during the memory test; The total completion time is: the time it takes for the subject to correctly click all the numbers from the first number clicked by the mouse to the time the subject correctly clicks all the numbers with the mouse; The segment duration is: the time it takes for the subject to correctly click the i-th number to correctly click the (i+1)-th number; the value range of i is greater than or equal to 1 and less than or equal to (N-1); The calculation formula for the segment duration is: ΔT[(i+1)-(i)]=T i+1 -T i (2) In formula (2), T i+1 is the time when the subject clicks the (i+1)th number; T i is the time when the subject clicks the i-th number; The path ratio is: the ratio of the length of the eye movement trajectory of the subject in the process of searching for the (i+1)th number after correctly clicking the i-th number to the straight-line distance between the i-th number and the (i+1)th number on the memory ability test interface; The calculation formula of the path ratio is: R[(i+1)-(i)]=S (i+1)-(i) / D (i+1)-(i) (3) In formula (3), S (i+1)-(i) D represents the length of the eye movement trajectory when the subject searches for the (i+1)th number after correctly clicking the i-th number; (i+1)-(i) Represents the straight-line distance between the i-th number and the (i+1)-th number on the memory ability test interface; The first click error serial number is: the serial number i corresponding to the number clicked incorrectly when the subject makes the click error for the first time; The calculation formula of the memory capacity is: Memory capacity = N × (ACC – 0.5) / 0.5 (4) In formula (4), N is the total number of numbers marked on all graphics during the subject's memory ability test; ACC is the recall accuracy; The number recall sequence deviation ρ is the degree of deviation between the order in which the subject actually clicks the numbers and the prescribed order when taking the memory ability test.

4. The method for memory ability assessment based on digital recall according to claim 3, characterized in that: The calculation process of the digital recall sequence deviation ρ specifically includes: The sequence corresponding to the click order specified when the subject takes the memory test is marked as X = [x1, x2, ..., x N ]; where x i is the i-th number in the sequence corresponding to the specified click sequence; where N is the total number of numbers corresponding to the specified click sequence; The sequence corresponding to the order in which the subject actually clicks the numbers when taking the memory test is marked as Y = [y1, y2, ..., y n ]; where y j is the jth number in the sequence corresponding to the order of the numbers actually clicked; where n is the total number of numbers corresponding to the order of the numbers actually clicked; According to the sequence corresponding to the specified click order and the sequence corresponding to the order of the actual clicked numbers, an N×n dimension distance matrix D is constructed; wherein the element d(i, j) of the distance matrix D is the number x i to the number y j The absolute value of the distance between them; A cumulative distance matrix C is constructed from the distance matrix D; wherein the element c(i, j) of the cumulative distance matrix C is the element d(i, j) of the distance matrix D plus the minimum value of the elements {c(i-1, j), c(i, j-1), c(i-1, j-1)} in the cumulative distance matrix C; the minimum value of the elements {c(i-1, j), c(i, j-1), c(i-1, j-1)} in the cumulative distance matrix C is the number x i With the number y j The minimum cumulative distance between two points; The value of the element c(N,n) in the cumulative distance matrix C is the degree of deviation between the order in which the subject actually clicks the numbers and the prescribed order when taking the memory ability test; When the order in which the subject actually clicks the numbers during the memory ability test is completely consistent with the prescribed clicking order, the number recall order deviation ρ is zero.

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