JP2006087833A - Method, program and device for inspecting recognizing function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recognizing function inspecting method capable of quantificating severity evaluation with a spatial perception impairment as an object, and to provide its program, and its device. <P>SOLUTION: When a person in charge of an inspection to inspect the brain function of a subject operates a personal computer 6 and starts the inspection of unilateral spatial neglect, an image generating part 6a generates image data including a visual stimulation, displays the generated image on LCD (liquid crystal display) 1, and presents the visual stimulation to the subject via a half mirror 4 and a recessed mirror 3. An ocular movement measuring part 6b detects an ocular movement under the presentation of the visual stimulation from the image data which is outputted from an imaging apparatus 2, detects the position of a gaze point relative to the visual stimulation, based on the ocular movement, and measures a deviation in the right and left direction of the gaze point position by each visual stimulation. A recognizing function evaluating part 6c evaluates severity with unilateral spatial neglect as an object by evaluating a difference between the right and left recognizing functions of the subject, based on the measurement result of the ocular movement measuring part 6b. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a brain function, in particular, a cognitive function test method, a cognitive function test program, and a cognitive function test apparatus for rehabilitation of spatial cognitive impairment due to cerebrovascular disorder and function recovery training.

  When the cerebral hemisphere on one side of the brain is damaged, a phenomenon occurs in which the stimulus on the other side of the lesion is not noticed and does not respond or does not go to the other side of the lesion. This phenomenon is called unilateral spatial neglect. In humans, symptom occurs when one side of the cerebral hemisphere is damaged, ignoring the object on the opposite side of the damaged side. There is a tendency and a tendency to gaze at one side of the subject. In order to effectively implement such rehabilitation and functional recovery training for spatial cognitive impairment, it is effective to aim for recovery step by step according to the severity of the disorder.

  For the simple examination of neglecting the half space, a written test using paper and pencil such as copying, peripheral segment test, and bisection test is simple and useful. It is difficult to quantify the severity assessment for purely neglected spatial neglect because of the effects of other impairments such as decline and other cognitive impairments. It was difficult to quantitatively grasp the degree.

Therefore, the effective visual field range is measured by deriving the horizontal and vertical eye movements and detecting only the high-speed movement components of the eye movements (see, for example, Patent Document 1), or the right eye movement and the left eye movement. Diagnosis of brain function and the like has been conventionally performed by detecting a difference from the eye movement of the eye (see, for example, Patent Document 2). Because it shows different characteristics from the left (right) same-named half-blind patients without ignorance, and tends to ignore the left and right sides and look at the other side (reference: Ishigo Sumio, “Hemi-side space ignorance and eye movements” "Abnormal", Nervous Progression, 1996, Vol. 40, No. 3), it was thought that the diagnosis of neglecting the hemispace was possible by measuring eye movement.
Japanese Patent No. 2705758 (paragraph numbers [0009] to [0016], FIGS. 1 to 4) JP 2001-321342 A (paragraph number [0040])

  Since eye movement is light and effortless, it is less affected by symptoms other than ignoring half-space, and by measuring the eye movement trajectory and gaze position, the subject's subjective response It was considered that objective evaluation of cognitive function that does not depend on it would be possible. However, even with eye movement measurements as described above, it is difficult to objectively evaluate cognitive functions, and it is difficult to quantify the severity assessment for spatial cognitive impairments such as unilateral spatial neglect. There are currently no indicators.

  The present invention has been made in view of the above reasons, and its purpose is to provide a cognitive function test method, a cognitive function test program, and a cognitive function test device that enable quantification of severity evaluation for spatial cognitive impairment. Is to provide.

  According to the first aspect of the present invention, a plurality of visual stimuli are presented at predetermined positions in the visual field of the subject in a predetermined order, and the position of the gazing point with respect to the visual stimuli is determined from the eye movement during the visual stimulus presentation. It detects, measures the shift | offset | difference of the gaze point position in the left-right direction, and evaluates the right-and-left difference of a test subject's cognitive function based on this measurement result.

  According to this invention, the objective evaluation of the spatial cognitive function that does not depend on the subjective answer of the subject can be quantified, and the severity evaluation for spatial cognitive impairment can be quantified. As a result, for example, the training effect can be objectively evaluated. Furthermore, the examination procedure can be automated, the examination time can be shortened, and the burden on the trainer and subject of spatial cognitive impairment can be reduced.

  The invention according to claim 2 provides a computer with a function of presenting a plurality of visual stimuli in a predetermined order at a position determined for each visual stimulus in the visual field of the subject, and a visual stimulus from an eye movement during the presentation of the visual stimulus. It is characterized in that a function of detecting a gaze point position relative to the eye and measuring a lateral shift of the gaze point position and a function of evaluating a left-right difference in the cognitive function of the subject based on the measurement result are realized.

  According to this invention, the objective evaluation of the spatial cognitive function that does not depend on the subjective answer of the subject can be quantified, and the severity evaluation for spatial cognitive impairment can be quantified. As a result, for example, the training effect can be objectively evaluated. Furthermore, the examination procedure can be automated, the examination time can be shortened, and the burden on the trainer and subject of spatial cognitive impairment can be reduced.

  The invention of claim 3 is a stimulus presentation means for presenting a plurality of visual stimuli in a predetermined order for each visual stimulus in the visual field of the subject, and eye movements during visual stimulus presentation to the visual stimulus. It comprises eye movement measurement means for detecting a gaze point position and measuring a lateral shift of the gaze point position, and cognitive function evaluation means for evaluating a left-right difference in the cognitive function of the subject based on the measurement result. And

  According to this invention, the objective evaluation of the spatial cognitive function that does not depend on the subjective answer of the subject can be quantified, and the severity evaluation for spatial cognitive impairment can be quantified. As a result, for example, the training effect can be objectively evaluated. Furthermore, the examination procedure can be automated, the examination time can be shortened, and the burden on the trainer and subject of spatial cognitive impairment can be reduced.

  The invention of claim 4 is characterized in that, in claim 3, the stimulus presenting means moves the visual stimulus continuously spatially within the visual field of the subject.

  According to this invention, a third party can objectively determine whether or not a subject is gazing at a visual stimulus.

  According to a fifth aspect of the present invention, in the fourth aspect, the eye movement measuring means determines whether or not the subject is tracking a visual stimulus that moves spatially and continuously in the visual field of the subject as a visual target. When tracking a visual stimulus as a visual target, calibration calculation of two coordinate systems of the coordinate system of the stimulus presentation unit and the coordinate system of the eye movement measurement unit is performed.

  According to the present invention, calibration work can be performed accurately.

  According to a sixth aspect of the present invention, in the fifth aspect, the stimulus presenting means presents a stationary visual stimulus after the calibration calculation, and the eye movement measuring means is a visual that is stationary with respect to the gazing point position. It is characterized by measuring the difference in the left-right direction from the position of the stimulus.

  According to this invention, the reliability of the evaluation result can be improved by performing the severity evaluation for spatial cognitive impairment in a state where accurate calibration is performed.

  The invention according to claim 7 comprises the answer input means for the subject to answer that the visual stimulus moving spatially continuously in the visual field has reached a predetermined position in claim 4, wherein the eye movement measuring means It is characterized by detecting the position of the gazing point at the time.

  According to the present invention, it is possible to determine whether or not the subject is really gazing at the target based on the difference between the gaze point position at the time of answering and the predetermined position in the left-right direction.

  The invention of claim 8 is characterized in that, in any of claims 3 to 7, each visual stimulus has a specific shape.

  According to the present invention, the subject's attention can be directed to the visual stimulus.

  The invention of claim 9 is characterized in that, in claim 3, the stimulus presentation means limits the presentation time of each visual stimulus.

  According to the present invention, the subject's attention can be directed to the visual stimulus.

  According to a tenth aspect of the present invention, in any one of the third to ninth aspects, the stimulus presentation means presents a plurality of visual stimuli having different shapes at different timings, and the eye movement measuring means is provided for each visual stimulus. Then, each gazing point position when the subject gazes at the same position in the visual field is detected, and a difference in the left-right direction between each gazing point position is measured.

  According to this invention, the severity evaluation for spatial cognitive impairment can be quantitatively performed based on the difference in the left-right direction between the positions of gazing points.

  The invention of claim 11 is characterized in that, in any of claims 3 to 10, the plurality of visual stimuli have different colors.

  According to the present invention, the subject's attention can be directed to the visual stimulus.

  According to a twelfth aspect of the present invention, in any one of the third to eleventh aspects, the color of each visual stimulus changes with time.

  According to the present invention, the subject's attention can be directed to the visual stimulus.

  The invention of claim 13 is characterized in that, in claim 10, one of the visual stimuli is a visual stimulus that displays nothing.

  According to the present invention, it is possible to simplify the visual stimulus generated by the stimulus presenting means.

  A fourteenth aspect of the present invention is characterized in that, in any one of the third to ninth aspects, the stimulus presentation means presents a visual stimulus whose size changes with time.

  According to this invention, the concentration level of the subject can be improved.

  According to a fifteenth aspect of the present invention, in the fourteenth aspect, the eye movement measuring means detects each gaze point position when the subject gazes at the same part of each visual stimulus having a different size, and It is characterized in that the difference between the left and right directions is measured.

  According to the present invention, the severity evaluation for spatial cognitive impairment can be quantitatively performed based on the bias of the gazing point position and the size of the visual stimulus, and further, the size of the attention area of the subject can be determined. Can be evaluated.

  According to a sixteenth aspect of the present invention, in any one of the third to fifth aspects, the stimulus presentation means presents visual stimuli arranged at symmetrical positions in the visual field of the subject at different timings, and the eye movement measurement means includes Further, it is characterized in that a gaze point position for each visual stimulus is detected and a difference in fluctuation in the left-right direction of each gaze point position is measured.

  According to the present invention, it is possible to quantitatively evaluate the severity of spatial cognitive impairment based on the difference in the horizontal direction of the fluctuation of each gazing point position.

  The invention of claim 17 is characterized in that, in any of claims 3 to 16, the relative position between the stimulus presentation means and the eye movement measurement means is fixed.

  According to the present invention, the relative position between the visual object space coordinate system and the eye movement measurement coordinate system due to the movement of the subject does not occur, and the reliability of the measurement result can be ensured by one calibration. It is possible to accurately measure the bias of the gazing point in the visual space and the bias of the gazing point with respect to the target target.

  The invention of claim 18 is characterized in that, in claim 17, the goggles to be worn on the head of the subject are used as a casing.

  According to the present invention, the relative position between the stimulus presentation unit and the eye movement measurement unit is fixed, and the relative position between the visual target space coordinate system and the eye movement measurement coordinate system is shifted by the head movement of the subject. Absent.

  As described above, in the present invention, it is possible to quantify the objective evaluation of the spatial cognitive function that does not depend on the subjective answer of the subject, and it is possible to quantify the severity evaluation for spatial cognitive impairment. The cognitive function testing method, the cognitive function testing program, and the cognitive function testing device can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 shows the configuration of a cognitive function testing device, which includes a liquid crystal display (LCD) 1 that presents visual stimuli to a subject, an imaging device 2 that images the subject's eyeball P, and the front of the subject's eyes. A concave mirror 3 located at the center, a half mirror 4 located between the eyeball P of the subject and the concave mirror 3, an infrared light LED 5 located near the eyeball P of the subject and irradiating the eyeball P with infrared light, A personal computer 6 and an output unit 7 are provided.

  The LCD 1 displays an image, reflects it by the half mirror 4 and presents a virtual image formed by the concave mirror 3 to the position in front of the subject's eyes through the half mirror 4 (see the solid line arrow in FIG. 1). It is controlled by a video generation unit 6a described later.

  The imaging device 2 includes an infrared transmission filter 2a and a CMOS area image sensor (CMOS sensor) 2b. The infrared light irradiated from the infrared LED 5 to the eyeball P of the subject is reflected by the eyeball P. Further, after being reflected by the half mirror 4 and passing through the filter 2a, it is input to the CMOS sensor 2b, and the CMOS sensor 2b acquires an image of the eyeball P of the subject (see the broken line arrow in FIG. 1). Further, the infrared LED 5 is arranged so as not to disturb the visual field of the subject. Furthermore, since the emission wavelength of the infrared light LED 5 is in the infrared wavelength region, the light from the infrared light LED 5 is not sensed by the subject, and the subject's anxiety can be reduced.

  In the present embodiment, two sets of LCD 1, imaging device 2, concave mirror 3, half mirror 4, and infrared LEDs 5 and 5 are provided, and LCD 1, imaging device 2, concave mirror are provided for each eye of the subject. 3, each pair of the half mirror 4 and the infrared light LEDs 5 and 5 correspond to each other.

  The personal computer 6 includes a video generation unit 6a, an eye movement measurement unit 6b, and a cognitive function evaluation unit 6c. Here, when a tester who performs a brain function test on the subject operates the personal computer 6 to start a test for ignoring the half-side space, the video generation unit 6a generates video data including visual stimuli and generates the generated video. Is displayed on the LCD 1 and a visual stimulus is presented to the subject via the half mirror 4 and the concave mirror 3. Then, the eye movement measuring unit 6b detects the eye movement during presentation of the visual stimulus from the video data output from the imaging device 2, detects the position of the gazing point with respect to the visual stimulus from the eye movement, and performs the injection for each visual stimulus. Measure the deviation of the viewpoint position in the left-right direction. The cognitive function evaluation unit 6c evaluates the degree of severity for ignoring the half space by evaluating the left-right difference in the cognitive function of the subject based on the measurement result of the eye movement measurement unit 6b.

  The eye movement detection method by the eye movement measuring unit 6b may use the fact that the movement amount of the eyeball is directly proportional to the movement amount of the pupil center position when the movement range of the eye movement is very small. When the movement range of the eye movement is large, it is necessary to know the rotation radius of the eyeball in advance. However, it is very difficult to actually measure the rotation radius of the eyeball. Calculations may be simplified using 5 mm (reference: Kazuo Koga, Yukio Nakamizo, Ryoji Osaka), “Experimental psychology of eye movement”, Nagoya University Press.

  The output unit 7 includes a display device such as a display device or a printer, and displays the evaluation result of the severity of ignoring the half space obtained from the cognitive function evaluation unit 6c. From the display of the output unit 7, the person in charge of the examination or the subject can easily read the evaluation result.

  Here, the LCD 1, the concave mirror 3, the half mirror 4, and the video generation unit 6 a constitute stimulus presentation means, and the imaging device 2, half mirror 4, infrared light LED 5, and eye movement measurement part 6 b constitute eye movement measurement means. And the cognitive function evaluation part 6c comprises a cognitive function evaluation means.

  2 (a) to 2 (c) show a video (see FIGS. 2 (a) and 2 (b)) generated by the video generation unit 6a and presented to the subject, and a gaze order of visual stimuli presented by the video (FIG. 2). (See (c)), and the screen by the concave mirror 3 exists as a virtual image at a position of X = 1.4 m in front of the eye in the field of view of the subject, and the horizontal viewing angle is 45.0 deg centering on the subject. The front angle of the subject is 0 deg, the right direction is a positive viewing angle, and the left direction is a negative viewing angle. In FIG. 2 (a), one linear optotype A is presented as a visual stimulus in the horizontal direction (left and right direction) at the center position in the vertical direction (up and down direction) on the screen. The left and right lengths are formed equally.

  In FIG. 2B, the viewing angles θ1 = 20.0 deg, θ2 = 10.3 deg, θ3 = 0 deg, θ4 = −10.3 deg from the right in the horizontal direction at the center position in the vertical direction on the screen by the concave mirror 3. , Θ5 = −20.0 deg, round targets B1 to B5 are presented as visual stimuli. A plurality of these circle targets B1 to B5 are not presented at the same time, and only one of the circle targets is presented.

  At the time of the inspection, first, a horizontal linear visual target A is presented on the screen by the concave mirror 3, and the subject is instructed to gaze at the center position of the linear visual target A. The gazing point position at this time is M0. After the linear visual target A is presented and a predetermined time elapses, the circular visual target B1 is presented at the position of the viewing angle θ1 = 20.0 deg, and the subject is instructed to gaze at the circular visual target B1. The gazing point position at this time is R0. Next, after a predetermined time has elapsed since the circular target B1 was presented, the circular target B2 is presented at the position of the viewing angle θ2 = 10.3 deg, and the subject is instructed to gaze at the circular target B2. The gazing point position at this time is R1. After that, the circular targets B3, B4, and B5 positioned at the viewing angles θ3 = 0 deg, θ4 = −10.3 deg, and θ5 = −20.0 deg are sequentially presented at regular intervals, respectively. The viewpoint positions are C0, L0, and L1. Then, after a predetermined time has elapsed since the circular visual target B5 is presented, the linear visual target A is presented, and the subject is instructed to gaze at the central position of the linear visual target A. The gazing point position at this time is M1. Hereinafter, the round targets B1, B2, B3, B4, and B5 are sequentially presented at regular time intervals, and the gazing point positions at the time of presenting each round target are R2, R3, C1, L2, and L3.

  Here, when the subject is healthy, it is possible to gaze at the substantially central position of the linear optotype A when instructed to gaze at the central position of the linear optotype A, and the gaze point positions M0, M1, and C0. , C1 are almost the same in the screen (the gazing point positions M0, M1, C0, C1 are ideally exactly the same in the screen).

  Next, the graph of FIG. 3 shows the measurement results of eye movement when the visual stimulus shown in FIGS. 2A to 2C is used for a patient with neglected left half space caused by cerebrovascular disorder. It can be seen that the eye movement occurs according to each gazing point position. Note that a steep change in the vertical direction of the graph indicates that blinking has occurred.

  Here, attention is paid to the gazing point positions M0, C0, M1, and C1. The gazing point positions M0 and M1 are positions when the central position of the linear visual target A is watched, and the gazing point positions C0 and C1 are positions when the circular target B3 positioned at the viewing angle θ3 = 0 deg is watched. Although the gazing point positions M0, C0, M1, and C1 are ideally exactly the same in the coordinate position on the screen as described above, each gazing point position has a lateral shift. In FIG. 3, a deviation D0 which is a difference in the left-right direction between the gazing point positions M0-C0 and a deviation D1 which is a difference in the left-right direction between the gazing point positions M1-C1 are generated with substantially the same magnitude.

  The deviations D0 and D1 are caused by the difference in the horizontal direction between the linear visual target A and the circular visual target B3 that are visual stimuli. Specifically, the linear target A is a target having a spread in the left-right direction, and the round target B3 is a small target having no spread in the left-right direction, and between these two targets, It can be said that the size of the attention target area of the visual space required for the subject is different. For this reason, in a patient with neglected left side space that presents a symptom that the attention area in the left side view space is missing, the attention area that extends in the left and right direction, such as the linear optotype A, is ignored and cannot be recognized. The left vision space that is not suitable for attention becomes relatively large. On the other hand, in a visual target that does not spread in the horizontal direction, such as the circular target B3, the attention area that extends in the left-right direction is also small. Becomes smaller. It is considered that the difference in the lateral extent between the linear visual target A and the circular visual target B3 appears as deviations D0 and D1.

  That is, the deviations D0 and D1 are the results of quantifying the degree of ignorance of the patients with neglected hemispace, and can be said to be the quantification of the severity evaluation for ignoring hemispace. In addition, eye movement is light and effortless, and it is performed unconsciously, so that the effects of symptoms other than ignoring the half space are small. Therefore, the eye movement measuring unit 6b measures the deviations D0 and D1, and the cognitive function evaluation unit 6c can objectively evaluate the cognitive function without relying on the subject's subjective answer based on the deviations D0 and D1. The severity evaluation for unilateral spatial neglect can be performed quantitatively, and for example, an objective evaluation of the training effect becomes possible.

  Here, it is not easy even for a healthy person to keep a close eye on a target that does not change, and it is accompanied by fatigue for patients with neglected space. Therefore, it may be possible to encourage the subject to pay attention by changing the properties of the target (reference: Kazuo Koga, Eye Movement Experiment Mini Handbook, Human Science, Frontier Series-2000, Labor Science Research Institute Publishing Department, 2000), as the method, each target of the linear target A and the circular targets B1 to B5 is presented in different colors, or the target color is changed over time while each target is presented. Then, the subject's attention can be directed to the target. Moreover, the subject's attention can be directed to the visual target by limiting the presentation time of the visual target and presenting the visual target for a moment and making it difficult to see the visual target intentionally. In this way, it is expected that median vision in the center of the eyeball of the subject with respect to the target will be continued by setting each index to a different color, changing the color of the target, or limiting the presentation time. it can.

  The eye movement measuring unit 6b measures the time during which the subject is gazing at the target from the detected eye movement, and compares the gaze time with the presentation time of the target, so that the subject can actually select the target. Whether or not the user is gazing can be determined, and if the severity evaluation is performed only when it is determined that the target is being gazed, the reliability of the evaluation result is improved.

  Furthermore, if the said inspection procedure is automated, test | inspection time can be shortened and the tester in charge of a spatial cognitive disorder, a training instructor, and a test subject can be eased.

  Moreover, not only the straight target A and the round targets B1 to B5 but also an empty screen on which no target is presented is displayed, and the subject is instructed to gaze at the center of the empty screen. Severity evaluation for ignoring the half space may be performed based on the gazing point position with respect to the screen and the deviation of the gazing point positions M0, C0, M1, and C1.

  The personal computer 6 that controls the above-described cognitive function test operation incorporates an operation program for executing the cognitive function test operation in advance.

(Embodiment 2)
The cognitive function testing device of this embodiment is shown in FIG. 1 as in the first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted.

  In the first embodiment, when the gaze point position R0 when gazing at the round target B1 located at the right end of the screen and the gaze point position L1 when gazing at the round target B5 located at the left end of the screen are compared ( 3), the gazing point position L1 (see the area E1) is more stable than the gazing point position R0 (see the area E0) even if the blink that shows a steep change is removed. It can be seen that it is unstable because it cannot be fixed. In this way, by measuring the gaze stability at each gazing point position of the target arranged symmetrically in the visual field, that is, by measuring the difference in fluctuation in the left and right direction of each gazing point position by the eye movement measurement unit 6b, The cognitive function evaluation unit 6c can evaluate the stability of the cognitive function from the measurement result and quantitatively perform the severity evaluation for the neglected half space.

(Embodiment 3)
The cognitive function testing device of this embodiment is shown in FIG. 1 as in the first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted.

  FIG. 4 shows an image generated by the image generation unit 6a and presented to the subject, and an equilateral triangle target is presented as a visual stimulus, and the equilateral triangle target is an equilateral triangle target F1 → It changes from F2 to F3 to F4 and gradually decreases. When the size of the equilateral triangle target changes, the presentation position of each center of the equilateral triangle targets F1 to F4 does not change in the screen by the concave mirror 3, and the subject gazes at the center of the equilateral triangle target. Instructed.

  When the subject gazes at the center of the visual target, the subject confirms the central position of the visual target from the visual information of the top, bottom, left, and right within the visual field. In the case of the equilateral triangle target of this embodiment, it is considered that the center position of the target is determined with reference to the positions of the three sides. That is, the subject needs to recognize the positions of the three sides in advance in order to determine the center position of the equilateral triangle target.

  However, when there is a partial spatial recognition failure like a patient with neglected spatial space, the positions of all three sides of the equilateral triangle target are not necessarily recognized. If the position recognition of the three sides is abnormal, it can be expected that a bias occurs when the center position of the equilateral triangle target is watched. The degree of this deviation may vary depending on the size of the equilateral triangle target. In this case, the size of the attention area in the visual space may be reflected in the size of the equilateral triangle target. That is, the cognitive function evaluation unit 6c uses the quantitative value of the gaze point position relative to the center position of the equilateral triangle target detected by the eye movement measurement unit 6b and the size of the equilateral triangle target to determine the attention area of the subject. The size can be quantified, and this can be used to evaluate the severity of unilateral spatial neglect.

  Also, if each target of equilateral triangle targets F1 to F4 is presented in a different color, or if the color of the target is changed over time during the presentation of each target, the attention of the subject will be used as the target. Can be directed. Moreover, the subject's attention can be directed to the visual target by limiting the presentation time of the visual target and presenting the visual target for a moment and making it difficult to see the visual target intentionally.

  Furthermore, not only the equilateral triangle targets F1 to F4 having different sizes but also display an empty screen on which no target is presented, and instruct the subject to gaze at the center of the empty screen, The eye movement measurement unit 6b detects the gaze point position at that time, and the cognitive function evaluation unit 6c detects the gaze point position detection result for the empty screen and the gaze point position detection result for the equilateral triangle targets F1 to F4. In addition, severity assessment for unilateral spatial neglect may be performed. This empty screen is equivalent to using a sufficiently large equilateral triangle target.

  Moreover, it can also be expected that the degree of concentration of the subject is improved by presenting the visual target whose size changes as a visual stimulus.

  In this embodiment, an equilateral triangle target is used, but a target having another shape such as a linear target may be used.

(Embodiment 4)
The cognitive function testing device of this embodiment is shown in FIG. 1 as in the first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted.

  FIG. 5 shows an image generated by the image generation unit 6a and presented to the subject. A circular target is presented as a visual stimulus, and the circular target is moved in the vertical direction and leftward from the right end of the screen. The movement in the direction is repeated and the circular target G1 → G2 →. . . It moves spatially continuously to the left end of the screen via each position of G9 → G10. The subject is instructed to track the circular target that moves spatially continuously in the visual field, and the eye movement measurement unit 6b detects the position of the point of gaze at that time. It is known that eye movement also becomes a continuous movement when gazing at a spatially moving target, and conversely without a target that moves spatially continuously, I know that doesn't happen. Such eye movement is called sliding eye movement.

  By the way, in the eye movement measurement, the eye movement used when the eye movement measurement unit 6b measures the eye movement and the coordinate system (visual target space coordinate system) of the stimulus presentation means used when the image generation part 6a presents the image. It is necessary to perform calibration calculation of two coordinate systems in advance with the coordinate system of the measuring means (eye movement measurement coordinate system). However, once the calibration is performed, the relative positional relationship between the two coordinate systems may be shifted due to the head movement of the subject, and it is necessary to force the subject to limit the head movement to prevent this deviation. There will be a burden on the subject. Furthermore, when calibration deviation occurs, the reliability of the measurement result also decreases.

  Conventionally, calibration is performed by causing the subject to see the left and right targets on the screen, but if one target is not watched due to the symptom of neglecting the half space, it is difficult to perform accurate calibration. Furthermore, it is not easy to determine what the subject is gazing at, and it is unclear whether or not the position of the gazing point has been accurately detected at the calibration stage, and it is determined whether or not the calibration has been performed accurately. It can be difficult.

  However, the appearance of the slidable eye movement is evidence that the subject is gazing at the visual target. This means that it is possible to solve a problem that has been very difficult in the past, in which a third party can objectively determine whether or not the patient with neglected hemispace is really gazing at the target. That is, as shown in FIG. 5, when sliding eye movements occur in the subject according to the direction of movement of the target when the target that moves spatially continuously is presented, the subject correctly gazes at the target. it is conceivable that.

  In order to derive which position on the screen on which the test subject is presenting the visual target, the correspondence between the two coordinate systems of the visual object space coordinate system and the eye movement measurement coordinate system is clarified. However, in this embodiment, the appearance of the slidable eye movement is used for calibration for gazing point calculation performed by the eye movement measuring unit 6b. That is, since it is difficult for a patient who exhibits a unilateral spatial neglect symptom to determine whether or not he / she is really gazing at a target, it is considered that calibration work is also difficult. However, the eye movement measurement unit 6b of the present embodiment tracks and gazes the visual target as a visual target when a sliding eye movement that tracks the target moving continuously spatially appears. Therefore, the calibration work of the two coordinate systems, the visual object space coordinate system and the eye movement measurement coordinate system, can be performed accurately.

  Then, after performing the calibration operation by the sliding eye movement, the severity evaluation for ignoring the half space is performed using the stationary visual stimulus as in any of the first to third embodiments.

  In addition, if the color of the round target is changed with time during the presentation of the circular target shown in FIG. 5, the subject's attention can be directed to the target, and more accurate calibration calculation can be expected.

(Embodiment 5)
The cognitive function testing device of this embodiment is shown in FIG. 1 as in the first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted.

  In eye movement measurement, in order to determine the visual target that the subject is viewing, it is necessary to calibrate the two coordinate systems of the visual object space coordinate system and the eye movement measurement coordinate system in advance. If the subject's head is fixed and the subject space coordinate system is fixed to a coordinate system unrelated to the subject's position, even if calibration work is performed, the subject's head movement will occur after calibration. The relative position between the object space coordinate system and the eye movement measurement coordinate system is shifted, and recalibration is required.

  Therefore, if a cognitive function testing device in which the relative positions of the two coordinate systems of the object space coordinate system and the eye movement measurement coordinate system are fixed is used, the calibration work can be performed once regardless of the head movement of the subject. Well, there is no need to recalibrate with head movement (reference: Hideo Fukunaga, 5 others, "Video nysmograph with built-in stimulation screen", Matsushita Electric Engineering Technical Report, 2004, Vol 52, No. 1). For example, if the LCD 1, the imaging device 2, the concave mirror 3, the half mirror 4, and the infrared LED 5 are housed in a goggle housing and mounted on the subject's head, the stimulus presentation means and the eye movements The relative position with the measurement means is fixed, and the relative position between the visual target space coordinate system and the eye movement measurement coordinate system is not shifted, the gaze point bias in the subject's visual space, The bias of the gazing point is accurately measured.

(Embodiment 6)
The cognitive function testing device of this embodiment is provided with an answer input unit 6d in the personal computer 6 shown in FIG. 1, and its configuration is shown in FIG. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  First, as shown in FIG. . . It moves spatially continuously from the right end to the left end of the screen via the positions G9 → G10. Then, the subject is instructed to operate the answer input unit 6d to input an answer when the round target has reached a predetermined position, and the eye movement measurement unit 6b receives the answer from the subject. , And the difference in the left-right direction between the position of the point of gaze and the position instructed in advance to operate the answer input unit 6d is measured. Then, if the measurement result of the difference in the left-right direction is equal to or smaller than a predetermined value, it can be determined that the subject is gazing at the target, and only when it is determined that the subject is gazing, the first to third embodiments. The reliability of the evaluation results can be improved by performing the severity evaluation for ignoring half-space, which is the same as either one.

  Although the eye movement measurement unit 6b compares the gaze time with the presentation time of the visual target as shown in the first embodiment, for example, the subject is determined to be gazing at the visual target. When the determination result in the present embodiment using the answer input unit 6d is a result that the subject is not gazing at the target, it can be considered that the subject's motor function is abnormal.

It is a figure which shows the structure of the cognitive function test | inspection apparatus of Embodiment 1 of this invention. (A)-(c) It is a figure which shows the image | video shown to a test subject same as the above, and the gaze order of a visual stimulus. It is a figure which shows the measurement result of the eyeball movement of Embodiment 1, 2 of this invention. It is a figure which shows the image | video shown to the test subject of Embodiment 3 of this invention. It is a figure which shows the image | video shown to the test subject of Embodiment 4 of this invention. It is a figure which shows the structure of the cognitive function test | inspection apparatus of Embodiment 6 of this invention.

Explanation of symbols

1 LCD
2 Imaging device 2a Filter 2b CMOS sensor 3 Concave mirror 4 Half mirror 5 Infrared LED
6 Personal Computer 6a Video Generation Unit 6b Eye Movement Measurement Unit 6c Cognitive Function Evaluation Unit 7 Output Unit P Eyeball

Claims (18)

A plurality of visual stimuli are presented in a predetermined order at a position determined for each visual stimulus in the visual field of the subject, and the position of the gazing point is detected by detecting the position of the gazing point with respect to the visual stimulus from the eye movement during the visual stimulus presentation. A cognitive function test method characterized by measuring a shift in the left-right direction and evaluating a left-right difference in the cognitive function of a subject based on the measurement result. A function for presenting a plurality of visual stimuli to a computer at a predetermined position in the visual field of the subject in a predetermined order and a position of a gazing point with respect to the visual stimulus from the eye movement during the visual stimulus presentation are detected. A cognitive function testing program that realizes a function of measuring a horizontal shift of a gaze point position and a function of evaluating a left-right difference of a subject's cognitive function based on the measurement result. A stimulus presentation means for presenting a plurality of visual stimuli in a predetermined order at a position determined for each visual stimulus in the visual field of the subject, and detecting a gaze point position with respect to the visual stimulus from the eye movement during the visual stimulus presentation A cognitive function testing device comprising: an eye movement measuring unit that measures a lateral shift of a gazing point position; and a cognitive function evaluating unit that evaluates a left-right difference in the cognitive function of a subject based on the measurement result. 4. The cognitive function testing device according to claim 3, wherein the stimulus presentation means moves the visual stimulus spatially and continuously within the visual field of the subject. The eye movement measuring means determines whether or not the subject is tracking a visual stimulus that moves spatially continuously in the visual field of the subject as a visual target, and the subject is tracking the visual stimulus as a visual target. 5. The cognitive function testing apparatus according to claim 4, wherein calibration calculation is performed on two coordinate systems, the coordinate system of the stimulus presentation unit and the coordinate system of the eye movement measurement unit. The stimulus presenting means presents a stationary visual stimulus after the calibration calculation, and the eye movement measuring means measures a difference in the left-right direction between the point of interest and the position of the stationary visual stimulus. The cognitive function testing device according to claim 5. A test subject is provided with an answer input means for answering that a visual stimulus that moves spatially continuously in a visual field has reached a predetermined position, and the eye movement measuring means detects a position of a gazing point at the time of answer. The cognitive function testing device according to claim 4. The cognitive function testing device according to claim 3, wherein each of the visual stimuli has a specific shape. The cognitive function testing device according to claim 3, wherein the stimulus presentation unit limits a presentation time of each visual stimulus. The stimulus presentation means presents a plurality of visual stimuli having different shapes at different timings, respectively, and the eye movement measurement means has each gaze point when the subject gazes at the same position in the field of view for each visual stimulus. The cognitive function testing device according to any one of claims 3 to 9, wherein the cognitive function testing device according to any one of claims 3 to 9, wherein a position is detected and a difference in the left-right direction between each gaze point position is measured. The cognitive function testing device according to claim 3, wherein the plurality of visual stimuli have different colors. The cognitive function testing device according to claim 3, wherein the color of each visual stimulus changes with time. The cognitive function testing device according to claim 10, wherein one of the visual stimuli is a visual stimulus that displays nothing. The cognitive function testing device according to claim 3, wherein the stimulus presentation unit presents a visual stimulus whose size changes with time. The eye movement measuring means detects each gaze point position when the subject gazes at the same part of each visual stimulus having a different size, and measures a lateral difference between the gaze point positions. The cognitive function testing device according to claim 14. The stimulus presenting means presents visual stimuli arranged at symmetrical positions in the visual field of the subject at different timings, and the eye movement measuring means detects a point of gazing point for each visual stimulus, 6. The cognitive function testing device according to claim 3, wherein a difference in fluctuation in the left-right direction of the viewpoint position is measured. The cognitive function testing device according to any one of claims 3 to 16, wherein a relative position between the stimulus presentation unit and the eye movement measurement unit is fixed. 18. The cognitive function testing device according to claim 17, wherein a goggle to be worn on the subject's head is used as a casing.

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