JP2004275619A - Method for communicating visual image stimulus to brain wave animus and system used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for communicating a visual image stimulus to brain wave animus by which a person can clearly communicate with other people consciously without using his hands, legs, mouth, eyelids, or the like, and a simple system used for the same. <P>SOLUTION: This method is characterized in that a subject to be tested sees letters, words, or drawings on a display for a short period of time according to a pre-established procedure and information that the subject wants to communicate is selected by detecting whether or not a positive potential (P300) has been generated by the stimulus in the brain waves of the subject between 300 and 600 msec after the beginning of the stimulus. Further, the visual system for communicating the image stimulus to brain wave animus comprises a display 1 that shows the "stimulus" to the subject to be tested according to the pre-established procedure; an electroencephalograph 3 that can detect the brain waves of the subject to be tested and its detection terminal 2; an analog/digital converter 4; and a control section that computes, displays, and records obtained data. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
[Industrial applications]
The present invention relates to an image stimulus-electroencephalogram communication method and a system used for the method, in which a person can communicate another person's intention to another person without using his / her hands and feet and without uttering words.
[0002]
[Conventional technology]
Conventional people can communicate their intentions to others by uttering words as speech, writing characters using a keyboard, pencil, brush, pen, mechanical pencil, etc., or by gestures or blinks I went. However, patients with illness such as amyotrophic lateral sclerosis, or those with severe physical disability due to injury, may be unable to speak because their hands, feet, mouth, eyelids, etc. do not move as intended. There is a problem in that it is impossible to do so, it is impossible to signal with the eyelids, it is not possible to write, or it is not possible to move the body without operating the keyboard etc. and to communicate the intention.
[0003]
For example, Japanese Patent Application Laid-Open No. H10-262943 has proposed a system for intentionally transmitting the intention of a person to another person without using his / her hand, foot, mouth, eyelid, and the like. However, what is proposed in this gazette is "detecting brain wave data at a plurality of locations, detecting changes in brain waves as surface distribution information, and analyzing the time-series change pattern of the surface distribution information and the motion of each part of the human limb in advance. In this method, it is not easy to communicate the intention by measuring proposed brain waves.
[0004]
The reason is that there are spontaneous electroencephalograms, which are electrical activities that persist regardless of stimuli, and electroencephalograms induced by stimuli that look and hear the screen, which are recorded with the former spontaneous electroencephalograms The strength and cycle of the potential are different in each part of the brain, the latter stimulus is a very small response, and the potential evoked by it is a brain potential that is not directly related to the stimulus except in special cases This is because it is buried in and difficult to identify.
[0005]
[Problems to be solved by the invention]
The present invention solves the above-described problems, and an image stimulation-brain wave communication method that can consciously and clearly convey a person's intention to others without using hands, feet, mouth, eyelids, and the like. , And a simple system used for the same.
[0006]
[Means for Solving the Problems]
That is, according to the present invention, the subject is shown a character, a phrase, or a figure (hereinafter, referred to as “stimulus”) on the display in a preset procedure, and the stimulus is positive for the subject's electroencephalogram during 300 to 600 msec after the start of the stimulus. This is an image stimulation-electroencephalogram intention communication method characterized by selecting contents to be communicated by detecting whether or not a potential (P300) is generated.
[0007]
It is preferable to use the brain wave of the parietal lobe as the brain wave.
[0008]
The present invention also provides a display 1 adapted to show a subject a "stimulus" according to a preset procedure, an electroencephalograph 3 capable of detecting an electroencephalogram of the subject and its detecting end 2, an analog / digital converter 4, and The present invention relates to an image stimulation-electroencephalogram communication system comprising a control unit for processing, displaying, and recording the obtained data.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
First, an image stimulus-electroencephalogram communication system of the present invention will be described in detail with reference to examples.
As shown in FIG. 1, an image stimulation-electroencephalogram communication system according to one embodiment of the present invention includes a display 1, an electroencephalograph 3 capable of detecting a subject's electroencephalogram, a detection end 2, an analog / digital converter 4, And a control unit for calculating, displaying, and recording the obtained data.
[0010]
In FIG. 1, reference numeral 1 denotes a display which is a display screen. The display 1 and the control unit 4 can be of an integrated structure, regardless of the type of display such as a CRT display, a fluorescent tube display, and a liquid crystal display.
[0011]
As the screen presented on the display 1, the pre-assigned communication contents are displayed as "stimuli" such as characters or figures. The “stimulus” can be printed out on paper and output by connecting a printing printer to the control unit 4.
[0012]
The “stimulus” displayed on the display surface may be automatically and sequentially displayed on the display by software, and may be automatically and intermittently erased. Further, the display color of the “stimulus” on the display, the color of the surrounding paint, or the brightness may be changed so that the display position can be specified. The display time or the time for erasing can be arbitrarily changed.
[0013]
Next, the method of the present invention will be described. The method of the present invention is a method focusing on the electroencephalogram positive potential (P300) generated during 300 to 600 msec after the start of stimulation. An example of an electroencephalogram P300 is shown in FIG.
[0014]
Specifically, by presenting the subject with the "stimulus" on the display for a short time in a preset procedure, and detecting whether or not a positive potential (P300) is generated by the "stimulus" in the subject's brain waves, And selecting what you want to communicate.
[0015]
The measurement of the electroencephalogram is performed at any measurement position on the head shown in FIG. This position is based on the International 10-20 Law. In addition, it is preferable that the electrodes at these positions are used as search electrodes, and measurement is performed with reference to the connection between both earlobes. It is particularly preferable to measure the brain wave of the parietal lobe (the position of PZ in FIG. 2) among the measurement positions of the head because P300 clearly appears for the target intended by the subject.
[0016]
Various known devices can be used as devices for measuring brain waves. For example, a device such as an electroencephalograph or a biological signal amplifier can be used.
[0017]
The electroencephalogram measured by the above method is sent to a personal control unit via an analog / digital (A / D) converter 3 as shown in FIG. I'm sorry. This brain wave may be displayed in a chart over time on a display, for example, or may be converted into a sound or light emission when P300 occurs. The intention transmitting partner can recognize the subject's intention by judging whether or not P300 is generated in the electroencephalogram using an electroencephalogram chart, voice, and light.
[0018]
Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
[0019]
Embodiment 1
Ten healthy men aged 22 to 24 years were set as subjects. The subject sat in a chair with the eyes open and rested, and received visual stimulus from an image presented on a display about 1 m away at a position substantially at the level of eyes. At this time, the electroencephalogram was measured, and the electroencephalogram was taken into a personal control unit via an analog / digital (A / D) converter.
[0020]
As for the electroencephalogram, the electroencephalogram at the position of PZ on the parietal lobe was measured using the measurement electrode as a probe electrode and the connection between both earlobes as a reference electrode.
[0021]
In order to communicate, a character string was first presented on the display screen by the control unit software (the upper diagram in FIG. 4). Next, only a specific character string is selected, and the selected character string is highlighted (this character string is shown by changing the color of the color image line by line as shown in the lower diagram of FIG. 4). It was projected on. The image stimulus presentation time was 300 msec, and the presentation interval was 1500 msec. The sampling interval was 1 msec, and brain waves from 100 msec before stimulation to 1000 msec after stimulation were recorded.
[0022]
Specifically, as shown in the lower diagram of FIG. 4, "Tatsutsuto" was first displayed on the screen, "Kakikukeko" was displayed 15 seconds later, and "Aioeo" was displayed 15 seconds later. The subject showed a response to the electroencephalogram P300 by successively looking at the character string and looking at the character string to be transmitted and having the intention to transmit.
[0023]
For example, a subject who wants to convey “head” first looks for the character “a”. Therefore, pay attention to the character string "Aioe". The examiner pays attention to the character string "AIUEO" that responded to P300, and sequentially displays each character in the character string on the display at regular intervals, and identifies the character from which the brain wave of P300 appears in the display. Do. Specifically, as shown in FIG. 5, the brightness of a specific character among the characters “A”, “I”, “U”, “E”, and “O” is changed on the display, surrounded by a frame, Specific characters are sequentially displayed by a method such as filling or inverting. The subject responds with an intention to convey his / her intention when “a” of these characters is displayed. As a result, the brain wave of P300 is emitted at the moment when the character of "a" is displayed.
[0024]
Record this character elsewhere on the display. Hereinafter, the above operation is repeated, and a sentence "head" is created. The difference in the electroencephalogram measured for the presence or absence of the P300 reaction between the target character and the other characters is as shown in FIG.
[0025]
By repeatedly displaying the screen as described above and finally recording and displaying the target character string in a part of the screen, the text intended by the subject can be displayed on the screen. Thus, the intention of the communication candidate can be shown on the display using only the fluctuation of the brain wave.
[0026]
Embodiment 2
The second embodiment is a system that asks questions about desires that occur regularly on a daily basis, for example, meals, urination, turning on / off a light, and the like, and inquires about intentions. Characters as shown in the upper part of FIG. 6 are displayed on the screen of the display. After a certain period of time, the characters at the four corners, "Yes", "No", "I do not know", "End", change the color of the character at regular intervals or change the color of the fill, by either method Display a specific group of characters. Then, after a certain time, for example, the color of the character fill changes clockwise. In this display, the character in which the P300 response to the subject's electroencephalogram is regarded as the intention of the subject to transmit. When the subject is not interested in this question, a P300 response occurs to the subject's brain wave at the "end", so that the next question can be moved to.
[0027]
Embodiment 3
In the above, the case of using characters has been described. However, the same result as the case of using characters was obtained when a diagram in which pictures and characters were mixed as shown in FIG. 7 was used.
[0028]
【The invention's effect】
According to the present invention, since it is possible to communicate using brain waves, there is a language disorder, and a handicapped person whose hands, feet, mouth, eyelids, etc., do not move as intended, Since it is possible to communicate the intention to another person using the diagram, there is an effect that the intention can be surely transmitted.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing an outline of an image stimulation-electroencephalogram communication system of the present invention.
FIG. 2 is a schematic view showing a preferred position for measuring an electroencephalogram in the image stimulation-electroencephalogram communication method of the present invention.
FIG. 3 is a diagram showing one example of a measured brain wave in the image stimulation-brain wave communication method of the present invention.
FIG. 4 is a diagram showing an example of a character string displayed on a display in the embodiment of the image stimulation-brain wave communication method of the present invention.
FIG. 5 is a diagram showing an example of a screen for selecting a character in the embodiment of the image stimulation-electroencephalogram communication method of the present invention.
FIG. 6 is a diagram showing another example of a character string displayed on a display in the embodiment of the image stimulation-electroencephalogram communication method of the present invention.
FIG. 7 is a diagram showing an example in which a character string displayed on a display and a figure are combined in the embodiment of the image stimulation-electroencephalogram intention communication method of the present invention.

Claims (3)

The subject is shown a character, a phrase, or a figure (hereinafter referred to as “stimulus”) on the display by a preset procedure, and a positive potential (P300) is applied to the subject's brain wave by stimulation during 300 to 500 msec after the start of stimulation. An image stimulation-electroencephalogram intention communication method characterized by selecting contents to be communicated by detecting whether or not it has occurred. The method according to claim 1, wherein the brain wave is a brain wave of a parietal lobe. A display 1 that allows a subject to show “stimulation” in a preset procedure, an electroencephalograph 3 that can detect a subject's brain waves and its detection end 2, an analog / digital converter 4, and the obtained data An image stimulation-electroencephalogram communication system comprising a control unit for performing arithmetic processing, displaying, and recording.

Images