Driving aptitude checking device

Abstract

To provide a driving aptitude checking device that can quantitatively check whether an object person has necessary attention ability.SOLUTION: A driving aptitude checking device 100 includes: a brain wave measurement device 20 for measuring a brain wave of an object person US; a stimulation generation device 31 for providing the object person US with a test stimulus ST including a first specific stimulus FS1 having a specific frequency that arouses extrinsic attention when measuring the brain wave; and a determination device 11a for evaluating the extrinsic attention from the power of a brain wave corresponding to the specific frequency in the brain wave relating to the extrinsic attention.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a driving aptitude confirmation device that confirms a subject's level of attention based on electroencephalograms. [Background technology]

[0002] A driving assistance device is disclosed that detects a driver's electroencephalogram (EEG) signal and estimates the amount of attention allocated to driving by the driver from the amplitude of the event-related potential of the EEG signal (see Patent Document 1). The device in Patent Document 1 grasps the driver's level of distraction from EEG. However, there are different types of attention, such as intrinsic attention and extrinsic attention, and it is unclear whether the level of distraction grasped by the device in Patent Document 1 is appropriate for determining driving aptitude. In addition, the amount of attention allocated by a driver varies depending on the driver's physical condition and driving conditions on that day. Furthermore, because the amount of attention allocated differs from driver to driver, it is difficult to determine whether to entrust the driver with driving tasks that are highly urgent or important. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-180873 Summary of the Invention

[0004] The present invention has been made in consideration of the above points, and has an object to provide a driving aptitude confirmation device that can quantitatively confirm the driving aptitude required by a subject.

[0005] In order to achieve the above object, the driving aptitude confirmation device of the present invention comprises an electroencephalogram (EEG) measuring device that measures the electroencephalogram of a subject, a stimulus generating device that applies a test stimulus including a first predetermined stimulus of a specific frequency that arouses the subject's extrinsic attention when measuring the EEG, and a judgment device that evaluates the extrinsic attention from the power of the EEG corresponding to the specific frequency in the EEG related to the extrinsic attention.

[0006] According to the driving aptitude confirmation device, the extrinsic attention required by the subject can be quantitatively confirmed by evaluating the extrinsic attention evoked by the first predetermined stimulus to which the subject is not paying attention. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a conceptual diagram illustrating an example of use of a driving aptitude confirmation device. [Figure 2] FIG. 2 is a front view showing a part of the driving aptitude confirmation device. [Figure 3] FIG. 1 is a conceptual block diagram illustrating a driving aptitude confirmation device. [Figure 4] FIG. 10 is a diagram illustrating a test stimulus displayed on the display screen of the stimulus generator. [Figure 5] 10(A) to 10(C) are diagrams showing examples of the display screen of the stimulus generation device when application software is executed. [Figure 6] FIG. 10 is a diagram showing the frequencies of electroencephalograms occurring in electroencephalogram data. [Figure 7] FIG. 10 is a diagram showing the waveform and amplitude of extracted electroencephalogram data. [Figure 8] 4 is a flowchart illustrating an example of an operation of the driving aptitude confirmation device. [Figure 9] 4 is a flowchart illustrating an example of an operation of the driving aptitude confirmation device. DETAILED DESCRIPTION OF THE INVENTION

[0008] [Embodiment] Hereinafter, the driving aptitude confirmation device of this embodiment will be described with reference to the drawings.

[0009] Fig. 1 is a conceptual diagram illustrating an example of use of the driving aptitude confirmation device 100. Fig. 2 is a front view showing a part of the driving aptitude confirmation device 100. Fig. 3 is a conceptual block diagram illustrating the driving aptitude confirmation device 100.

[0010] The driving aptitude confirmation device 100 shown in FIGS. 1 to 3 can quantitatively confirm the amount of attention required by the subject US from electroencephalogram data, out of the amount of attention allocated to the subject US. The amount of attention allocated is the total amount of attention resources available to the subject US. The subject US can pay attention within the range of the amount of attention allocated, and attention decreases when the range is exceeded. The amount of attention allocated varies from person to person and changes depending on the situation, proficiency, physical condition, etc. The total amount of attention is composed of the amount of attention related to each task, i.e., the amount of attention resources. Therefore, the amount of attention resources also varies from person to person and changes depending on the situation, proficiency, physical condition, etc. In this embodiment, the attention required by the subject US is, for example, the attention required to drive a train. If the amount of attention allocated is composed of the attention resources allocated to driving and the surplus attention resources, it is thought that as driving becomes more difficult, the attention resources allocated to driving increase, and when the surplus attention resources disappear, human error becomes more likely to occur.

[0011] The attention required by the subject US consists of extrinsic and intrinsic attention. Extrinsic attention refers to the momentary attention of the subject US when a stimulus appears in a location where the subject US is not currently paying attention. For example, extrinsic attention refers to the subject US recognizing a change in a traffic signal or a person or vehicle entering the tracks. Intrinsic attention refers to the subject US directing their attention to a specific location. For example, intrinsic attention refers to looking at the tracks in the direction of their line of sight while driving. As described above, attentional resource amounts vary from person to person. However, if the amount of each attentional resource meets certain conditions, it can be determined that the subject US has the necessary attentional capacity. Based on the above, the driving aptitude verification device 100 evaluates the extrinsic and intrinsic attention of the subject US using electroencephalogram data. This allows for quantitative confirmation of the extrinsic and intrinsic attention required by the subject US.

[0012] The subject US is, for example, a train driver, and in this case, the attention required for the driver in terms of driving ability can be evaluated. The subject US may also be other crew members, such as a conductor. Furthermore, the driving aptitude confirmation using the driving aptitude confirmation device 100 is not limited to train crew members, but may also be applied to crew members related to other vehicles, such as cars and airplanes.

[0013] The driving aptitude confirmation device 100 is installed at a station, etc. Driving aptitude confirmation using the driving aptitude confirmation device 100 is performed before boarding the train.

[0014] The driving aptitude confirmation device 100 includes a device main body 10, an electroencephalogram measuring device 20, an output device 30, and an input device 40.

[0015] As shown in Fig. 1 etc., the electroencephalogram measuring device 20 measures the electroencephalogram of the subject US. The electroencephalogram measurement is carried out for about 1 to 2 minutes. The measurement results of the electroencephalogram measuring device 20 are recorded as electroencephalogram data in a storage device 12 (see Fig. 3) of the device main body 10, which will be described later.

[0016] The electroencephalogram measuring device 20 is a simple electroencephalogram, for example, an earphone-type electroencephalogram 21. The earphone-type electroencephalogram 21 has ear tips 21a inserted into the left and right ears of the subject US as electrodes, and acquires electroencephalograms from the ear canals. The earphone-type electroencephalogram 21 is capable of communicating with the device main body 10 via short-range wireless communication such as Bluetooth (registered trademark). The electroencephalogram measuring device 20 may be any device that measures electroencephalograms, and may be, for example, a head-mounted simple electroencephalogram.

[0017] The measured electroencephalograms are sampled so that they can be processed by a control device 11 (see FIG. 3) of the device main body 10, which will be described later. The electroencephalogram data is collected at a sampling rate of, for example, 200 Hz to 500 Hz. The electroencephalogram data undergoes various data processing such as noise removal using a filter, baseline correction, averaging, and frequency analysis.

[0018] As shown in FIG. 3, the device main body 10 includes a control device 11 and a storage device 12.

[0019] The control device 11 controls the operations of the electroencephalogram measuring device 20, the output device 30, the storage device 12, etc. The control device 11 has a determination device 11a. The determination device 11a is one function of the control device 11 that operates using corresponding application software. The determination device 11a evaluates the attention required of the subject US from electroencephalograms (electroencephalogram data). Specifically, the determination device 11a evaluates the attention from the electroencephalograms of the subject US to which a predetermined stimulus has been applied. This allows the determination device 11a to quantitatively confirm the predetermined level of attention from the electroencephalograms. Details of the determination device 11a will be described later.

[0020] The storage device 12 stores various application software programs that can be executed by the driving aptitude confirmation device 100. The storage device 12 also stores a database related to the processing in the driving aptitude confirmation device 100.

[0021] As shown in FIG. 2 and other figures, the output device 30 is a stimulus generator 31 that applies a test stimulus ST to the subject US during electroencephalogram measurement. The stimulus generator 31 as the output device 30 is, for example, a display device such as a monitor. The stimulus generator 31 displays the test stimulus ST on a display screen 31a at a predetermined timing through the operation of application software by the control device 11 shown in FIG. 3. Here, the control device 11 outputs information regarding the time or timing of the stimulus occurrence to the determination device 11a, triggered by the output of an image signal to the stimulus generator 31. The trigger corresponds to a reference point for the reaction time of steady-state visual evoked potentials (SSVEP) related to exogenous attention or a reference point for the appearance of an event-related potential P300 related to intrinsic attention.

[0022] The input device 40 detects the subject US's response to a predetermined stimulus. The input device 40 has one or more input members 41. The input device 40 is, for example, a keyboard. The input device 40 may also be a button device. As will be described in detail later, when a first predetermined stimulus FS1 that attracts extrinsic attention is displayed on the stimulus generating device 31, the subject US performs an operation of pressing the input member 41, for example, the enter key 41b. Furthermore, when a second predetermined stimulus FS2 that attracts intrinsic attention is displayed on the stimulus generating device 31, the subject US performs an operation of pressing the input member 41, for example, the space key 41a.

[0023] Fig. 4 is a diagram illustrating the test stimulus ST displayed on the display screen 31a of the stimulus generator 31. Figs. 5(A) to 5(C) are diagrams illustrating examples of the display on the display screen 31a of the stimulus generator 31 when application software is executed. For convenience of explanation, Fig. 4 shows a state in which all test stimuli ST are lit, but Figs. 5(A) to 5(C) show displays according to the situation. The dotted triangular lines indicate a state in which the image is flashing.

[0024] In a driving aptitude task described below, two types of test stimuli ST are displayed on the display screen 31a of the stimulus generation device 31. As shown in Fig. 4 etc., the test stimuli ST include a first test stimulus ST1 related to the estimation of extrinsic attention and a second test stimulus ST2 related to the estimation of intrinsic attention.

[0025] The first test stimulus ST1 for the exogenous attention task is composed of a steady stimulus 71 and an idiopathic stimulus 72.

[0026] As shown in Figures 4 and 5(A), the steady-state stimulus 71 is a blinking stimulus of a predetermined frequency that is constantly output. On the display screen 31a, the steady-state stimulus 71 is displayed, for example, in the line of sight of the subject US. The steady-state stimulus 71 is, for example, a blinking display of a landscape (railroad tracks RL, sleepers TI, horizon HZ, etc.), that is, a blinking display of a landscape. The steady-state stimulus 71 is used to confirm whether the subject US's attention is directed toward the idiopathic stimulus 72. The frequency of the steady-state stimulus 71 is, for example, 15 Hz. Note that the frequency of the steady-state stimulus 71 can be changed as appropriate as long as it is different from the frequency of the idiopathic stimulus 72 or an integer multiple thereof.

[0027] As shown in Figures 4 and 5(C), the spontaneous stimulus 72 is a first predetermined stimulus FS1 of a specific frequency that attracts the subject US's extrinsic attention. The spontaneous stimulus 72 is, for example, a flashing image displayed at a predetermined timing in a location different from the landscape display, which is the steady stimulus 71, i.e., a spontaneous flashing display. The spontaneous stimulus 72 is displayed in a smaller area than the steady stimulus 71. The frequency of the spontaneous stimulus 72 is, for example, 8 Hz. The display time of the spontaneous stimulus 72 is, for example, 10 to 16 seconds. The frequency of the spontaneous stimulus 72 can be changed as appropriate as long as it is different from the frequency of the steady stimulus 71 or an integer multiple thereof.

[0028] The size, color, shape, and location of the spontaneous stimulus 72 can be changed as appropriate. By changing the size, etc., of the spontaneous stimulus 72, the difficulty of the stimulus, i.e., the difficulty of the task, can be changed. For example, the difficulty can be increased by reducing the size of the spontaneous stimulus 72, using a less obvious color, changing the display location, etc. By changing the difficulty of the spontaneous stimulus 72 in this way, it is possible to quantitatively evaluate exogenous attention as the amount of exogenous attention resources possessed by the subject US.

[0029] As shown in Figures 4, 5(A), and 5(B), the second test stimulus ST2 for the intrinsic attention task is composed of a first gaze stimulus GS1 and a second gaze stimulus GS2. The second test stimulus ST2 is displayed on the display screen 31a, for example, at the line of sight of the subject US. The second test stimulus ST2 is displayed at a gaze point EP, which is narrower than the steady stimulus 71 of the first test stimulus ST1. The first gaze stimulus GS1 and the second gaze stimulus GS2 are displayed in the same location. Note that the first gaze stimulus GS1 and the second gaze stimulus GS2 may be displayed at slightly different positions so as not to impair the gaze of the subject US.

[0030] The first gaze stimulus GS1 is a standard stimulus that is displayed frequently in the task of intrinsic attention. The first gaze stimulus GS1 is, for example, a random display of numbers (specifically, 1 to 9) at a high frequency. The first gaze stimulus GS1 is displayed in a blinking manner. The frequency of the first gaze stimulus GS1 is, for example, 1 Hz.

[0031] The second gaze stimulus GS2 is a deviant stimulus that is distinguished from the first gaze stimulus GS1 in the intrinsic attention task and is displayed at a lower frequency than the first gaze stimulus GS1. The second gaze stimulus GS2 is a second predetermined stimulus FS2 that arouses the intrinsic attention of the subject US. The second gaze stimulus GS2 is, for example, a random display of alphabets (specifically, A to X) at a low frequency. The second gaze stimulus GS2 is displayed in a flashing manner. The frequency of the second gaze stimulus GS2 is, for example, 1 Hz.

[0032] In the above, the first gaze stimulus GS1 and the second gaze stimulus GS2 may be distinguishable images and may be changed as appropriate. The first gaze stimulus GS1 and the second gaze stimulus GS2 may also be distinguishable sounds. In this case, the display of the second test stimulus ST2 on the display screen 31a of the stimulus generating device 31 can be omitted.

[0033] Tests or tasks related to driving aptitude will be described below. In this embodiment, a task related to extrinsic attention and a task related to intrinsic attention are conducted to check driving aptitude.

[0034] The following describes a task related to extrinsic attention in driving aptitude verification. In the task related to extrinsic attention, the driving aptitude verification device 100 presents the subject US with a first predetermined stimulus FS1 or the like that elicits extrinsic attention (see FIG. 5(C) and the like), and measures steady-state visual evoked potentials (EEGs) (brain waves generated in response to a visual response to a specific frequency) for the task. In the task related to extrinsic attention, a visual stimulus of a certain frequency is detected, and a peak occurs in the frequency band of the visual stimulus. Note that peaks also occur in frequency bands that are integer multiples of the frequency of the visual stimulus. In the task related to extrinsic attention, a steady visual stimulus (steady stimulus 71) and an spontaneous visual stimulus (spontaneous stimulus 72) corresponding to the first predetermined stimulus FS1 are generated, and the magnitude (peak intensity) of the peak in the frequency band of the spontaneous stimulus 72 is measured. The reaction time of the subject US is also measured based on the timing from the appearance of the spontaneous stimulus 72 to the occurrence of the peak in the frequency band of the spontaneous stimulus 72.

[0035] FIG. 6 is a diagram showing the frequency of electroencephalograms generated in electroencephalogram data (steady-state visual evoked potentials). In FIG. 6, the vertical axis represents frequency, and the horizontal axis represents time. In the example of FIG. 6, a spontaneous stimulus 72 (first predetermined stimulus FS1) is applied for a predetermined time during a steady stimulus 71. As shown in FIG. 6, a peak (specifically, solid line L1) appears consistently at frequency H1 of steady stimulus 71, and a peak (specifically, solid line L2) appears at a specific frequency H2 of spontaneous stimulus 72 a predetermined reaction time Δt after the spontaneous stimulus 72 is displayed. The reaction time Δt indicated by the electroencephalogram is, for example, 0.6 seconds.

[0036] The following describes a task related to intrinsic attention in driving aptitude confirmation. In the task related to intrinsic attention, the driving aptitude confirmation device 100 provides the subject US with a second predetermined stimulus FS2 or the like that arouses intrinsic attention (see FIG. 5(B) and the like), and measures the amplitude of the event-related potential P300, which is one waveform component of the event-related potential (electroencephalogram generated in relation to a specific event) for the task. The task related to intrinsic attention is also called a fixation task (oddball task). The fixation task or oddball task is a task in which two types of stimulus events (standard stimulus and deviant stimulus) are presented with different frequencies of occurrence, and the subject US is asked to respond only when the stimulus with a low frequency (deviant stimulus) appears. The stimulus may be a visual stimulus or an audio stimulus. In this embodiment, a visual stimulus is used as the stimulus.

[0037] Figure 7 shows the waveform and amplitude of extracted EEG data (event-related potential). A positive event-related potential P300 appears around 300 milliseconds after stimulation. In a fixation task or oddball task, when the same type of image (standard stimulus) is repeatedly displayed and a different type of image (deviant stimulus) is occasionally displayed, a positive potential change appears in the EEG around 300 milliseconds after viewing the different image (deviant stimulus).

[0038] The determination device 11a shown in FIG. 3 will be described in detail below.

[0039] The determination device 11a evaluates the extrinsic attention based on the response of the electroencephalogram (EEG) related to the extrinsic attention to a first predetermined stimulus FS1 shown in Fig. 5(C). Specifically, the determination device 11a evaluates the extrinsic attention based on the power (peak intensity) of the electroencephalogram corresponding to a specific frequency H2 in the steady-state visual evoked potential (VSP) for the first predetermined stimulus FS1. The determination device 11a also evaluates the extrinsic attention based on the reaction time Δt indicated by the electroencephalogram corresponding to the specific frequency H2.

[0040] The determination device 11a determines that the subject is receiving extrinsic attention or that the level of extrinsic attention is high if the power (peak intensity) of the EEG corresponding to the spontaneous stimulus 72 is greater than the determination threshold. Furthermore, the determination device 11a determines that the subject is receiving no extrinsic attention or that the level of extrinsic attention is low if the power (peak intensity) of the EEG corresponding to the spontaneous stimulus 72 is less than the determination threshold. The determination threshold is, for example, a general condition value required for driving. The determination threshold may be set for each subject's US. The threshold for each subject's US is set based on the median or average value of the measurement results obtained by measuring EEGs multiple times and over multiple days. It is considered that the threshold for each subject's US will be set to a consistent value, like body temperature, if the number of EEG measurements is increased. The power of the EEG will be reduced if cognitive function is impaired, such as when the reaction time Δt is slow.

[0041] The determination or evaluation of exogenous attention also takes into account the reaction time Δt corresponding to the spontaneous stimulus 72. The determination device 11a determines that exogenous attention is present or high when the reaction time Δt is smaller than the determination threshold. Also, the determination device 11a determines that exogenous attention is absent or low when the reaction time Δt is larger than the determination threshold.

[0042] By appropriately setting the judgment threshold to determine extrinsic attention, it is possible to grasp the degree of extrinsic attention possessed by the subject US, and quantitatively confirm the extrinsic attention required for the subject US.

[0043] The determination device 11a can check the amount of extrinsic attention resources by increasing the difficulty of the extrinsic attention task (for example, by changing the color, shape, size, appearance location, display time, etc.), thereby making it possible to check the extrinsic attention capacity more quantitatively.

[0044] In the extrinsic attention task, when a first predetermined stimulus FS1 is displayed, the subject US presses the enter key 41b as the input member 41 of the input device 40 shown in FIG. 2 etc. The act of the subject US pressing the input member 41 physically indicates the subject US's reaction to the extrinsic attention. The determination device 11a accepts the subject US's response via the input member 41 of the input device 40. The determination device 11a also takes into account the response time of the subject US to the first predetermined stimulus FS1 by pressing the input member 41 in the evaluation of extrinsic attention.

[0045] The determination device 11a confirms intrinsic attention from an electroencephalogram pattern in response to the second predetermined stimulus FS2 shown in Fig. 5(B) in the electroencephalogram related to intrinsic attention. Specifically, the determination device 11a evaluates intrinsic attention based on the magnitude of the amplitude of a positive event-related potential P300 that appears after the output of the second gaze stimulus GS2.

[0046] The determination device 11a determines that there is intrinsic attention or that the intrinsic attention is high when the value of the event-related potential P300 has a large amplitude relative to the baseline PL, as in the waveform EA shown in Figure 7. The determination device 11a also determines that there is no intrinsic attention or that the intrinsic attention is low when the value of the event-related potential P300 has a small amplitude relative to the baseline PL, as in the waveform NA. The baseline PL corresponds to a determination threshold at the time of determination. The determination threshold is, for example, a general condition value required for driving.

[0047] By appropriately setting the judgment threshold and determining intrinsic attention, it is possible to grasp the degree of intrinsic attention possessed by the subject US, and quantitatively confirm the intrinsic attention required for the subject US.

[0048] The determination device 11a can confirm the amount of intrinsic attention resources by increasing the difficulty of the intrinsic attention task (for example, by changing the color, shape, size, display time, etc.), thereby making it possible to confirm the intrinsic attention capacity more quantitatively.

[0049] In the intrinsic attention task, when the second predetermined stimulus FS2 is displayed, the subject US presses the space key 41a as the input member 41 of the input device 40 shown in FIG. 2 etc. The act of the subject US pressing the input member 41 physically indicates the subject US's response to the intrinsic attention. The determination device 11a accepts the subject US's response via the input member 41 of the input device 40. The determination device 11a also takes into account the reaction time of the subject US to the second predetermined stimulus FS2 by pressing the input member 41 in the evaluation of the intrinsic attention.

[0050] In the above, the extrinsic attention and the intrinsic attention may be calculated as numerical values ​​by applying a predetermined conversion formula to the electroencephalogram data. Also, the extrinsic attention and the intrinsic attention may be converted into levels.

[0051] The determination device 11a determines the driving suitability as being capable of driving, requiring caution, or not capable of driving, based on the evaluation of the extrinsic attention or intrinsic attention described above.

[0052] 8 and 9 are flowcharts illustrating an example of the operation of the driving aptitude confirmation device 100. The driving aptitude confirmation device 100 performs a task related to extrinsic attention (display of a first predetermined stimulus FS1) in the middle of a gaze task related to intrinsic attention. The driving aptitude confirmation device 100 acquires electroencephalogram data in real time. The electroencephalogram data undergoes predetermined data processing for processing in the determination device 11a.

[0053] First, the control device 11 starts a gaze point task and starts measuring the electroencephalogram of the subject US (step S11). Specifically, the control device 11 runs application software for verifying driving aptitude and displays a second test stimulus ST2 at the gaze point EP on the display screen 31a of the stimulus generator 31 shown in FIG. 5(A) and other figures. In the example shown in FIG. 5(A) and other figures, the gaze point task is performed on the horizon HZ to fix the gaze point EP of the subject US. In the gaze point task, the stimulus generator 31 randomly displays numbers (specifically, 1 to 9) as the first gaze stimulus GS1 with a high frequency (see FIG. 5(A)), and randomly displays alphabets (specifically, A to X) as the second gaze stimulus GS2 and second predetermined stimulus FS2 with a low frequency (see FIG. 5(B)).

[0054] When the display of the second test stimulus ST2 is switched at the gaze point EP (Yes in step S12), the control device 11, functioning as the determination device 11a, extracts an electroencephalogram corresponding to the event-related potential P300 (step S13). Specifically, as shown in Fig. 5(B), the display of the second test stimulus ST2 is switched from the first gaze stimulus GS1 to the second gaze stimulus GS2 in the stimulus generation device 31. In step S13, predetermined data processing is performed on the electroencephalogram data.

[0055] At this time, the determination device 11a accepts input of a response key related to intrinsic attention. When the second gaze stimulus GS2, which is the second predetermined stimulus FS2, is displayed, the subject US presses the space key 41a on the input member 41 of the input device 40. Pressing the space key 41a indicates the subject US's bodily response to the intrinsic attention. When the space key 41a is pressed, the input device 40 outputs the response of the subject US to the determination device 11a as input of a response key related to intrinsic attention.

[0056] When a response key input related to intrinsic attention is received (Yes in step S14), the control device 11, functioning as the determination device 11a, calculates a response time of the subject US to the second predetermined stimulus FS2 (second gaze stimulus GS2) (step S15). Specifically, the determination device 11a calculates the response time from the difference between the display timing of the second predetermined stimulus FS2 and the input timing of the input device 40.

[0057] When there is no response key input within a predetermined time (No in step S14), the control device 11, as the determination device 11a, adds a message indicating that there is no response key input to the electroencephalogram data (step S16). In this case, the response time of the subject US to the second predetermined stimulus FS2 is not taken into account in the evaluation of the intrinsic attention in the subsequent step S25.

[0058] When the timing for an external attention call arrives (Yes in step S17), the control device 11 causes the display screen 31a of the stimulus generator 31 to display the first predetermined stimulus FS1, that is, the spontaneous stimulus 72 (step S18), as shown in FIG. 5(C). When the spontaneous stimulus 72 is displayed, the steady stimulus 71 of the first test stimulus ST1 may continue to flash at a predetermined frequency, or may be lit only while the spontaneous stimulus 72 is displayed. In step S18, the second test stimulus ST2 may remain displayed.

[0059] If the timing for external attention has not arrived (No in step S17), the control device 11 continues the gaze task (step S19) and returns to step S12.

[0060] After step S18, the control device 11, functioning as the determination device 11a, extracts an electroencephalogram corresponding to a steady-state visual evoked potential (SSVEP) (step S20). In step S20, predetermined data processing is performed on the electroencephalogram data. The determination device 11a calculates the magnitude of the electroencephalogram peak at the frequency of the first predetermined stimulus FS1 (the spontaneous stimulus 72). The determination device 11a also calculates the reaction time Δt (see FIG. 6) from the difference between the display timing of the first predetermined stimulus FS1 and the appearance timing of the electroencephalogram peak at the frequency of the first predetermined stimulus FS1.

[0061] At this time, the determination device 11a accepts input of a response key related to extrinsic attention. When the idiosyncratic stimulus 72, which is the first predetermined stimulus FS1, is displayed, the subject US presses the Enter key 41b on the input member 41 of the input device 40. Pressing the Enter key 41b indicates the subject US's bodily response to the extrinsic attention. When the Enter key 41b is pressed, the input device 40 outputs the response of the subject US to the determination device 11a as input of a response key related to extrinsic attention.

[0062] When a response key input related to exogenous attention is received (Yes in step S21), the control device 11, functioning as the determination device 11a, calculates a response time of the subject US to the first predetermined stimulus FS1 (idiosyncratic stimulus 72) (step S22). Specifically, the determination device 11a calculates the response time from the difference between the display timing of the first predetermined stimulus FS1 and the input timing of the input device 40.

[0063] When there is no response key input within a predetermined time (No in step S21), the control device 11, as the determination device 11a, adds a message indicating that there is no response key input to the electroencephalogram data (step S23). In this case, the response time of the subject US to the first predetermined stimulus FS1 is not taken into account in the evaluation of the exogenous attention in the subsequent step S26.

[0064] 9, when a series of tasks for confirming driving aptitude is completed (Yes in step S24), the control device 11, functioning as the determination device 11a, evaluates the intrinsic attention (step S25). Specifically, the determination device 11a quantitatively estimates or determines the intrinsic attention from the electroencephalogram data and a determination threshold value related to the intrinsic attention. At this time, the determination device 11a also takes into account the response time calculated in step S15 in the intrinsic attention.

[0065] After step S25, the control device 11, functioning as the determination device 11a, evaluates the exogenous attention (step S26). Specifically, the determination device 11a quantitatively estimates or determines the exogenous attention based on the electroencephalogram data and a determination threshold value related to the exogenous attention. At this time, the determination device 11a also takes into account the response time calculated in step S22 in the exogenous attention.

[0066] Note that step S25 may be performed after step S26, or step S25 and step S26 may be performed in parallel.

[0067] When the series of tasks for checking driving aptitude are not completed (No in step S24), the control device 11, functioning as the determination device 11a, returns to step S12 shown in FIG.

[0068] The control device 11, functioning as the determination device 11a, determines the driving aptitude (step S27). Specifically, the determination device 11a determines the driving aptitude as being capable of driving, requiring caution, or not capable of driving, based on the evaluation of intrinsic attention in step S25 and the evaluation of extrinsic attention in step S26.

[0069] In the above, steps S13 and S20 may be performed after the task is completed (Yes in step S24).

[0070] According to the driving aptitude confirmation device 100, the extrinsic attention required for the subject US can be quantitatively confirmed by evaluating the extrinsic attention evoked by the first predetermined stimulus FS1 to which the subject US is not paying attention. Also, the intrinsic attention required for the subject US can be quantitatively confirmed by evaluating the intrinsic attention evoked by the second predetermined stimulus FS2 to which the subject US spontaneously focuses.

[0071] Generally, a subject US, such as a train driver, self-reports their health condition and illnesses before boarding a train. However, even if a subject US self-reports, accidents may occur due to the subject US's poor physical condition or illness, and self-reporting is insufficient to ensure safe and secure travel. The driving aptitude confirmation device 100 of the present invention can quantitatively confirm the extrinsic and intrinsic attention required of a subject US when driving a train, etc., and appropriately determine their driving aptitude.

[0072] [Other matters] The present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit and scope of the present invention.

[0073] In the above embodiment, the driving aptitude confirmation device 100 may evaluate only extrinsic attention. In this case, the stimulus generation device 31 displays only the first test stimulus ST1 related to extrinsic attention.

[0074] In the above embodiment, when the spontaneous stimulus 72 is displayed, the steady stimulus 71 may be hidden.

[0075] In the above embodiment, when the stimulus related to intrinsic attention is an audio stimulus, the stimulus generator 31 generates audio using earphones, speakers, or the like instead of a screen display.

[0076] In the above embodiment, the driving aptitude confirmation device 100 may omit the input device 40. In this case, the response time of the subject US to the first predetermined stimulus FS1 or the second predetermined stimulus FS2 is not taken into consideration in estimating the attentiveness. [Explanation of symbols]

[0077] 10...device main body, 11...control device, 11a...determination device, 12...storage device, 20...EEG measurement device, 21...earphone-type electroencephalograph, 30...output device, 31...stimulus generating device, 31a...display screen, 40...input device, 41...input member, 41a...space key, 41b...enter key, 71...steady stimulus, 72...episodic stimulus, 100...driving aptitude confirmation device, EP...point of gaze, FS1...first predetermined stimulus, FS2...second predetermined stimulus, GS1...first gaze stimulus, GS2...second gaze stimulus, H2...specific frequency, ST...test stimulus, ST1...first test stimulus, ST2...second test stimulus, US...subject

Claims

1. an electroencephalogram (EEG) measuring device for measuring the subject's electroencephalogram; a stimulus generating device that applies a test stimulus including a first predetermined stimulus of a specific frequency that arouses the subject's external attention during measurement of the electroencephalogram; a determination device that evaluates the exogenous attention based on the power of the electroencephalogram corresponding to the specific frequency in the electroencephalogram related to the exogenous attention; Equipped with Driving aptitude verification device.

2. the determination device evaluates the exogenous attention based on a reaction time indicated by the electroencephalogram corresponding to the specific frequency in a steady-state visual evoked potential in response to the first predetermined stimulus. The driving aptitude confirmation device according to claim 1.

3. the stimulus generator provides the subject with a second predetermined stimulus as the test stimulus that arouses intrinsic attention; the determination device evaluates the intrinsic attention from an electroencephalogram pattern in response to the second predetermined stimulus in the electroencephalogram related to the intrinsic attention. The driving aptitude confirmation device according to claim 1.

4. the stimulus generation device outputs, as the test stimulus, a first gaze stimulus to the subject's gaze point and a second gaze stimulus that is the second predetermined stimulus that is distinguished from the first gaze stimulus and is output at a frequency lower than that of the first gaze stimulus; the determination device evaluates the intrinsic attention based on the magnitude of the amplitude of a positive event-related potential that appears after output of the second gaze stimulus. The driving aptitude confirmation device according to claim 3.

5. an input device having one or more input members that detect the subject's response to the first predetermined stimulus and either the first predetermined stimulus or the second predetermined stimulus; the determination device receives a response from the subject using the input member, and takes into account a response time to the first predetermined stimulus or the second predetermined stimulus when evaluating either the extrinsic attention or the intrinsic attention. The driving aptitude confirmation device according to claim 1 or 3.

6. The determination device determines, based on the evaluation of the extrinsic attention or the intrinsic attention, that the driving suitability is one of capable of driving, caution, and incapable of driving. The driving aptitude confirmation device according to claim 1 or 3.

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