JPH0759742A - Brain wave diagnosis display system - Google Patents

Abstract

PURPOSE:To achieve an accurate judgment of mental condition of an examinee instantaneously by calculating a frequency-componental spectrum based on a brain wave data of the examinee to select and display a corresponding image from an image for display inputted previously. CONSTITUTION:A plurality of input images B generated previously corresponding to mental conditions are inputted into an image input section 100 to be stored into an image storage section 101. On the other hand, an analog waveform signal A of the brain wave is converted into a digital waveform data D with a waveform input section 102 to be applied to an image selection section 103. The image selection section 103 selects a display image S from among images G stored in the image storage section 101 based on the digital waveform data D to be applied to an image display section 104 for displaying the image. As a feature relating to the frequency of the brain wave can be obtained quantitatively depending on the mental condition of a man, the digital waveform data D is subjected to a frequency spectral analysis with a frequency spectrum analysis section 105 to accomplish the selection of image according to the results thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroencephalogram diagnostic display device, and more particularly to an electroencephalogram diagnostic display device characterized by selecting and displaying an image corresponding to the mental state of the subject based on the electroencephalogram data of the subject. is there.

[0002]

2. Description of the Related Art Conventionally, when confirming the mental state of a human, it is common to use analog waveform data in an electroencephalograph, and by reading the difference in the electroencephalogram pattern as shown in FIG. I was judging the condition.

[0003]

However, the above-mentioned conventional example has the following drawbacks.

That is, in the case of the method of confirming the electroencephalograph shown in the conventional example, it is extremely rare that the pattern change is clearly different as shown in FIG. 6, and the shape of the electroencephalogram pattern is always very complicated. Since it changes, it is difficult for an expert other than a doctor to accurately judge the mental state of a subject in an instant.

The present invention eliminates the above-mentioned conventional drawbacks and provides an electroencephalogram diagnostic display device capable of instantaneously and accurately determining the mental state of a subject even if not an expert.

[0006]

In order to solve this problem, the electroencephalogram diagnostic display device of the present invention comprises a waveform input means for converting an analog waveform signal of a human brain wave into digital waveform data and inputting the waveform. An image storage means for storing images,
Image selection means for selecting an image to be displayed from the plurality of images stored in the image storage means based on the digital waveform data, and image display means for displaying the selected image. And Here, the image selecting means calculates a spectrum for each frequency component from the digital waveform data, and makes a selection according to the spectrum. Further, the image storage means stores a plurality of display images corresponding to the waveform data of the electroencephalogram.

[0007]

First, in order to clarify the features of the present invention, the relationship between human brain waves and mental states will be briefly described.

Human brain waves usually change in a frequency band of 0 to 30 Hz, and there are the following four characteristic frequency bands in this frequency band.

1.5 to 3.5 Hz band → Delta (δ) wave 4.0 to 7.0 Hz band → Theta (θ) wave 8.0 to 13.0 Hz band → Alpha (α) wave 14.0 to 30 0.0 Hz band → beta (β) wave And these four types of EEG have the following characteristics related to human mental states. Delta wave is unconscious or deep sleep, Theta wave is "drowning" or dreaming state, Alpha wave is relaxed and awake, and beta wave is anxiety, worry, spirit It is said to appear in a state of physical excitement. In other words, the level of low-frequency brain waves becomes stronger as the human mental state stabilizes, and conversely, the level of high-frequency brain waves becomes stronger as the human mental state becomes more excited. . Further, when the levels of the four types of brain waves are almost the same and strong, it is said that the brain is in a mental diffusion state.

An object of the present invention is to reflect the mental state of a human in the selection of a display image by using such a human brain wave.

<Structure of EEG diagnostic display device> FIG. 1 is a block diagram showing a schematic structure of the EEG diagnostic display device of this embodiment.

Reference numeral 100 is an image input unit, 101 is an image storage unit, 102 is a waveform input unit, 103 is an image selection unit, and 104 is an image selection unit.
Is an image display unit. The input image B is the image input unit 100.
And is stored in the image storage unit 101. on the other hand,
The analog waveform signal A of the electroencephalogram is converted into digital waveform data D by the waveform input unit 102 and given to the image selection unit 103. The image selection unit 103 selects the display image S from the images G stored in the image storage unit 101 based on the digital waveform data D and supplies it to the image display unit 104 to display the image.

As described above, since the characteristics related to the frequency of the electroencephalogram can be quantitatively obtained according to the human mental state, as shown in FIG. 2, the digital waveform data D
It is also possible to decompose the frequency spectrum in the frequency spectrum decomposition unit 105 and select an image according to the result.

Therefore, the image S to be displayed is also created and registered in advance corresponding to each mental state, so that it can be selected from the images registered in the image storage unit 101 corresponding to a certain mental state. Then, it can be output and displayed on the image display unit 104.

FIG. 3 shows a specific example of the configuration of the electroencephalogram diagnostic display device of this embodiment.

In the figure, 1 is a person to be photographed.
A subject such as a landscape. Reference numeral 2 is a photographing device for photographing the subject, and for example, a camera is used. Reference numeral 3 denotes an image input device for inputting the photographed image, for example, a drum scanner is used. Reference numeral 3'denotes a command input device for giving an instruction to each part, for example, a keyboard is used. A data input device for inputting data such as the diameter of a 3 ″ dot, for example, a mouse is used.
Is a waveform input device for inputting an electroencephalogram, for example, an electroencephalograph is used.

A display device 4 is for displaying an input command, the input image, and a selected image, and for example, a CRT is used. 6 is the input image,
It is a file device for storing data input by a user and a display image. Reference numeral 7 denotes an arithmetic unit 7, which performs arithmetic processing for selecting a display image. A control device 5 controls the image input device 3, the command input device 3 ′, the data input device 3 ″, the waveform input device 8, the display device 4, the file device 6, and the arithmetic device 7.

The electroencephalogram diagnostic display device configured as described above will be described below in accordance with the data flow.

In FIG. 3, an input image corresponding to each electroencephalogram state photographed by the photographing device 2 is A / D (analog / digital) converted by the input device 3 and stored in the file device 6 to prepare an image for display. Is completed. Here, for convenience, red, green, and blue data forming each pixel of the input image are represented by R, G, and B, respectively. In addition, one pixel is data that can be expressed in each component of 8 bits, that is, 256 gradations, and the maximum brightness is 255 and the minimum brightness is 0, but the present invention is not limited to this. Then, the analog waveform data of the subject's electroencephalogram sent during a fixed time is A / D converted by the waveform input device 8 and stored in the file device 6 as digital waveform data. Then, based on this digital waveform data, a spectrum for each frequency component is created by the method described later and stored in the file device 6.
Then, using the result, the display device corresponding to each mental state is selected by the arithmetic device 7, and the display device 4 displays the selected image.

<Spectrum Calculation> Next, a method of calculating the spectrum for each frequency component of the electroencephalogram will be described.

First, as shown in FIG. 4, a measuring section of a waveform input device such as an electroencephalograph is attached to the head of a subject. Then, when the change in the potential between the electrodes A and B in the measuring unit over time is measured, a one-dimensional analog waveform signal as shown in FIG. 6 is obtained. Then, from this analog waveform signal, for example, a spectrum obtained by dividing the frequency band of 0 to F (H _Z ) into N frequency components is subjected to the discrete Fourier transform (D
Consider the case of calculation by FT: Discrete Fourier Transform. This DFT is a method usually used when a one-dimensional discrete signal is decomposed into frequency components and analyzed. Further, FFT (First Fourier Transform) is famous as a method of executing DFT with a small number of calculations.

First, when one sampling time of the waveform input device is T, N / T = F (formula -1) is established. Here, if the sampling interval of the waveform input device is set to Δt, Δt · N = T (formula-2) can be said due to the property that the number of inputs and the number of outputs in the DFT are equal. Therefore, from these two formulas, = 1 / F (Equation-3), and it can be seen that Δt does not depend on the division number N. Then, digital waveform data for every N sampling intervals as shown in FIG. 5 v (t) = v (i · Δt) (i = 0, 1, 2, 3, ..., N−1) (Equation-4) Then, the spectrum L (f) for each frequency component as shown in FIG. 6 can be calculated by the following equation using the DFT formula.

L (f) = L (K · F / N) = L (k / (Δt · N)) = Σv (i · Δt) · e × p (−jki / N) (Equation-5) ( k = 0, 1, ..., N−1 (where e × p (x) =
e ^x , j = sqrt (−1), and sqrt (x) is x
The calculation method of the spectrum for each frequency component based on the brain wave waveform data described above is
It is used in the image display processing described later.

<Diagnosis Display Processing Flowchart> FIG.
7 is a flowchart showing a diagnostic image display process in the present embodiment. The processing method will be described in detail below according to the flow of data.

(Step S1) The user displays five images corresponding to each of the five kinds of mental states of the delta wave state, theta wave state, alpha wave state, beta wave state, and mental diffusion state. Take an image with the image capture device,
For example, it is pasted on the drum of the drum scanner, and the information about the start of processing is sent from the command input device 3'to the control device 5.
Upon receiving the processing start command, the control device 5 sends a scan start command to the input device 3.

When the input device 3 receives the scan start command, it scans the image pasted on the drum and outputs, for example, 8-bit quantized data of the five input images. The control device 5 receives the five image data input by the input device 3 from the delta wave image, theta wave image,
The alpha wave image, the beta wave image, and the mental diffusion state image are assigned and stored in the file device 6 as a display image.

(Step S2) The control device 5 puts the data input device 3 "into a data input waiting state, and the user inputs each frequency of the delta wave, theta wave, alpha wave, and beta wave via the data input device 3". Bands (δ _min , δ _max ), (θ
_{min, θ max), (α} min, α max), (β mi n, β
_max ), the maximum frequency p (H) in the EEG spectrum
_Z ), the number of EEG frequency divisions (pieces), and the number of image displays M
(Times), the image display time s (seconds), and the threshold value q of the spectrum level for determining the mental diffusion state are input and stored in the file device 6.

(Step S2 ') The control unit 5 issues a command to the arithmetic unit 7 to calculate the sampling interval Δt of the waveform input unit 8 according to (Equation-3).

(Step S3) The controller 5 initializes the counter k with 1.

(Step S4) The control device 5 causes the waveform input device 8 to measure N brain waves at the sampling interval Δt, and the obtained brain wave digital waveform data v (t) = v.
(I · Δt), (i = 0, ..., N−1) are stored in the file device 6.

(Step S5) The controller 5 controls the digital waveform data v (i.Δt), (i =
0, ..., N−1), the spectrum L (k / (Δt ·
N)), (k = 0, ..., N−1) is calculated by the arithmetic unit 7 and stored in the file unit 6. Here, for convenience, let L (k / (Δt · N)) = L ′ (k).

(Step S6) The control unit 5 sends the file
Of L '(k), (K = 1, ..., N = 1) in the device 6,
δ_min ≦ k / (Δt · N) <δ_max In k where
And L '(k) is maximum (that is, maximum in delta wave)
(Value) k is calculated by the arithmetic unit 7, and k is calculated. _delta 
Is stored in the file device 6.

(Step S7) The controller 5 sends the file
Of L ′ (k), (K = 1, ..., N−1) in the device 6,
θ_min ≦ k / (Δt · N) <θ_max In k where
And L '(k) is maximum (that is, maximum in theta wave
(Value) k is calculated by the arithmetic unit 7, and k is calculated. _theta 
Is stored in the file device 6.

(Step S8) The control device 5 controls L '(k), (k = 1, ..., N-1) in the file device 6 to
Among k that satisfies α _min ≦ k / (Δt · N) <α _max , L ′ (k) becomes the maximum (that is, the maximum value in the alpha wave), and the arithmetic unit 7 is caused to calculate the value. K
_It is stored in the file device 6 as _alpha .

(Step S9) The control unit 5 controls the file
Of L ′ (k), (k = 1, ..., N−1) in the device 6,
β_min ≦ k / (Δt · N) <β_max In k where
And L '(k) is maximum (that is, maximum in beta wave
(Value) k is calculated by the arithmetic unit 7, and k is calculated. _betaWhen
And stores it in the file device 6.

(Step S10) The control unit 5 instructs the arithmetic unit 7 to make a decision 1: L '(k _delta )> q decision 2: L' (k _theta )> q decision 3: L '(k _alpha )> q Judgment 4: Four judgments of L '(k _beta )> q are performed, and the following processing is performed according to the result. (A) When all are true: The image for the mental diffusion state is used as the display image. (B) When even one is not true: L '(k _delta ),
L '(k _theta ), L' (k _alpha ), L '(k _beta )
Select the largest of the following and perform the following processing.

1) When L '(k _delta ) is maximum: The delta wave image is used as the display image.

2) When L '(k _theta ) is maximum: The theta wave image is used as the display image.

3) When L '(k _alpha ) is the maximum: The alpha wave image is used as the display image.

4) L '(k _beta ) is the maximum: The beta wave image is used as the display image.

(Step S11) The control device 5 displays the display image selected in step S10 on the display device for the time s.

(Step S12) The controller 5 increments the value of the counter k by 1.

(Step S13) The control unit 5 controls k and M
Are compared, and if k ≦ M, the process proceeds to step S4, and if k> M, the image display processing ends.

As an example of the displayed image, for example, the colors are distinguished, the delta wave image is achromatic, the theta wave image is blue, the alpha wave image is green, and the beta wave image is orange. If the image for the mental diffusion state is displayed in red, the mental state of the subject can be intuitively determined according to the color. Further, by changing the color density corresponding to the value of L ′, more detailed judgment can be made.

Images for delta waves are images of space, images for theta waves are images of the sea, images for alpha waves are images of forests, images for beta waves are images of cities, and images for mental diffusion. If the image is displayed as a photograph of the desert, it is possible to intuitively judge the mental state of the subject corresponding to the photograph.

In addition, although it is possible to simply represent the characters with abstract characters or symbols, it is preferable to use colors, photographs, etc. as those that can be intuitively judged by the viewer of the image.

Although the image is input from the positive film photographed by the drum scanner in this embodiment, the same effect can be obtained by inputting the image from the photographic print or the printed matter. Although the drum scanner is used as the image input device 3, the same effect can be obtained by directly inputting a three-dimensional object with a TV camera or the like.

In the present embodiment, the image as a still image input by the drum scanner is displayed on the CRT, but the present invention is not limited to this, and a moving image such as a video image may be used. That is, a plurality of moving images corresponding to respective mental states are recorded in advance on, for example, a video tape or a laser disk, and then the RS-23 is recorded.
It may be realized by playing back on a computer-controllable VCR or laser disc player via an interface such as 2C and displaying the image on a TV monitor or the like. This makes it possible to make a clearer decision.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0050]

According to the present invention, it is possible to provide an electroencephalogram diagnostic display device capable of accurately determining the mental state of a subject in an instant even if not a specialist. That is, the spectrum for each frequency component is calculated based on the waveform data of the subject's brain waves, and the result is used to select the corresponding image from the plurality of display images previously input and assigned to each mental state. By displaying it, the mental state of the subject can be accurately determined in an instant. Therefore, it is possible to accurately know the mental state of the subject even if the expert is not a doctor.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an electroencephalogram diagnostic display device according to an embodiment.

FIG. 2 is a diagram showing another example of an image selection signal.

FIG. 3 is a block diagram showing a specific configuration example of the electroencephalogram diagnostic display device of the present embodiment.

FIG. 4 is a diagram showing how an electroencephalogram is input in the present embodiment.

FIG. 5 is a flowchart showing a diagnostic display process of this embodiment.

FIG. 6 is a diagram showing a display example of an electroencephalograph.

FIG. 7 is a diagram showing A / D conversion of brain wave waveform data.

FIG. 8 is a diagram showing an example of a spectrum for each frequency component obtained by a discrete Fourier transform.

[Explanation of symbols]

 1 Subject 2 Image Capture Device 3 Image Input Device 3'Command Input Device 3'Data Input Device 4 Display Device 5 Control Device 6 File Device 7 Computing Device 8 Waveform Input Device 100 Image Input Unit 101 Image Storage Unit 102 Waveform Input Unit 103 Image Selection unit 104 Image display unit 105 Frequency spectrum decomposition unit

Claims (3)

[Claims] 1. A waveform input means for converting an analog waveform signal of a human brain wave into digital waveform data and inputting the same, an image storage means for storing a plurality of images, and the image storage means based on the digital waveform data. An electroencephalogram diagnostic display device comprising: an image selection unit that selects an image to be displayed from the plurality of images stored in the image storage unit; and an image display unit that displays the selected image. 2. The electroencephalogram diagnostic display device according to claim 1, wherein the image selection means calculates a spectrum for each frequency component from the digital waveform data and performs selection according to the spectrum. 3. The image processing apparatus according to claim 1, wherein the image storage means stores a plurality of display images corresponding to waveform data of brain waves.