JPS6338434A - Continuous display by display color of brain wave - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for continuously displaying electroencephalograms in graphical colors, and in particular, to a method for continuously displaying electroencephalograms in graphical colors, and in particular for each of a power spectrum graph, a frequency rhythm graph, a frequency appearance rate graph, a potential distribution diagram, and a potential fluctuation graph. By creating each frequency band of the graph in a different color and continuously displaying each graph in the form of a two-dimensional image of the brain waves up to a set number of times at regular intervals, it is easier to interpret the recorded fluctuating brain waves quantitatively and visually. This invention relates to a method for continuously displaying brain waves in graphical colors that can be easily understood.

(Prior art) Conventionally, electroencephalograms are generally recorded by deriving and recording changes in electrical activity exhibited by a group of brain cells over time using electrodes on the scalp. The waveform is represented by a waveform curve approximated by the height (amplitude μ■) and width (duration, period, milliseconds), and the frequency (
Hertz) is 1/period.

In order to read the brain waves from the waveforms recorded as above, it is generally accepted that brain waves are drawn at a width of 3α per second, so how many widths of the recorded waveforms are in 3 cm? The frequency is determined by measuring whether the signal enters with a scale, and the amplitude is determined by measuring the length with a scale and converting it into voltage.

(Problem to be solved by the invention) In order to read brain waves, it is necessary to read all pages of recorded brain waves, but since it takes time to read all of the many waves, it is necessary to read all the pages of the recorded brain waves. However, since there are individual differences in accurate reading, it is difficult to make quantitative judgments.

On the other hand, brain waves are analyzed by computer and color CRT
Some methods have been used to display potentials in different colors as a single still image, but the display is not quantitative, but only potential distribution information, and it is important to understand each frequency, which is an element in interpreting fluctuating brain waves. There is a lack of quantitative display of rhythmicity, appearance rate of each frequency, left-right difference due to the appearance of each frequency, potential distribution by desk frequency band, potential fluctuation, left-right difference due to potential, etc., and a single image of brain waves that fluctuates from moment to moment. There was an unclear drawback in understanding brain function by displaying static images based on potential distribution diagrams.

The present invention was completed as a result of research conducted in response to the fact that it is very difficult to analyze brain waves as described above, and even if the waveforms were shown to the general public and explained to them, they would not be able to understand. From the results, the recorded fluctuations can be recorded by continuously displaying the power spectrum graph, frequency rhythm graph, frequency appearance rate graph, potential distribution graph, and potential fluctuation graph in different colors at arbitrary fixed time intervals and up to an arbitrary set number of times. The purpose of this project is to provide a method for continuously displaying electroencephalograms by color, which can be easily grasped quantitatively and visually in interpreting the waveforms of electroencephalograms, and which is easy to explain and understand to the general public. be.

(Means for Solving the Problems) and (Operation) In other words, the present invention calculates the waveform of each electrode site inputted by an electroencephalograph at arbitrary fixed time intervals, and repeats the calculation up to an arbitrary set number of times. From the calculated values for each arbitrary fixed time, each graph of power spectrum graph, frequency rhythm graph, frequency appearance rate graph, potential distribution chart, and potential fluctuation graph is created an arbitrary set number of times, and every arbitrary fixed time up to an arbitrary set number of graphs are created. , is a method for continuously displaying electroencephalograms according to illustrated colors, which is characterized in that continuous display is performed according to illustrated colors.

The present invention will be explained in detail below.

A method for continuously displaying electroencephalograms in different colors according to the present invention will be explained in detail. Analog signals of 12 or 16 channels inputted from an electroencephalograph are sent to a personal computer via an interface device and analyzed, and the results are automatically displayed in a continuous manner according to color.

In electroencephalogram measurement, the electrodes apply the international method 10-20.
Installed using monopolar induction method with 2 or 16 channel input.

Moreover, a commercially available electroencephalograph can be used. A specific example is the IA96 model manufactured by Sanei Sokki. A personal computer is connected to the output terminal of the electroencephalograph via an interface device (built into the main body of the computer). The interface device has the function of converting the analog signal sent from the electroencephalogram needle into a digital signal and sending it to the personal computer.

The interface device consists of a 16CH multiplexer, preamplifier, 12bit A/D converter, intelligent control unit, etc.

The L6CH multiplexer is a device that switches 16 channels of input into inputs for each channel and takes in analog signals from the electroencephalogram, and the switching time is 50 μsec.

The preamplifier (full-scale amplifier) amplifies the signal taken in by the 16C) l multiplexer.

A 12-bit A/D converter (AD converter) converts the analog signal obtained from the preamplifier into a digital signal.

The intelligent control unit (data acquisition control device) controls the 16CH multiplexer, switches channels, activates the A/D converter, captures data for 16 channels, and sends the data to the personal computer.

An example of the specifications of the interface device is shown below.

Input channels: 16 channels Input impedance: 100Ω A/D conversion time: 200 μ/5ec A/D conversion accuracy: 12 bits Next, the personal computer will be explained.

The personal computer calculates the data sent from the interface device and creates a power spectrum graph, frequency rhythm graph, frequency appearance rate graph, potential distribution graph, and potential fluctuation graph, and displays the graphs in different colors up to an arbitrarily set number of times at regular intervals. Performs separate continuous display.

A personal computer consists of a computer main body, a color CRT, a keyboard, a printer, etc.

As the personal computer, a commercially available personal computer can be used. A specific example is NEC PC980
An example is type 1F.

An example of the specifications of a personal computer is: ○Main body main memory ROM 96K ByteRAM
640K Byte Size 420 (W) x 345 (D) x 300
(H) mm○ Output color CRT 12-inch display color 8 primary colors 83 colors including intermediate colors Screen configuration
Graph ink screen x 12 + number of characters displayed on the character screen
80 characters x 25 lines Size 365 (W) x 370 (D) x 300
()I) mm○Printer printing speed 80 characters/second Printing method Dot matrix impact bidirectional printing Number of prints 80 characters/line 66 lines/page size 410 (W) x 335 (D) x 125
(I() mmO operation keyboard Key layout Standard JTS numeric keypad included ○5-inch floppy disk, storage capacity equipped with 2 floppy disks
640K Bytex 2 Next, a method of recording electroencephalograms using this apparatus for continuous display in different colors will be described. 1st
The figure is a flowchart showing the flow of measurement data from the electroencephalograph. In FIG. 1, 12 channels or 16 channels of measurement data input from an electroencephalograph are sent to a personal computer via an interface device. The acquisition time is set to a constant calculation time.

Set arbitrarily up to 60 seconds in 5-second increments, and set the constant calculation time 1 to 60 times as the calculation condition for the amplitude above the baseline (vehicle peak at 2 minutes) or above and below the baseline (
Set whether to calculate vehicle peak.

Measurement data is then stored in the main memory of the personal computer in real time from the electroencephalograph via the interface device.

Number of channels: 12 or 16 channels Sampling cloth: 4.86m sec Number of sampling: 1024 points/channel The time series data stored in the main memory is processed using the fast Fourier transform method (F-F
-T) to convert into a complex Fourier series and calculate the power spectrum value a set number of times at regular intervals.

F-F-T calculation accuracy 32 bits Frequency resolution 0.2 Hz Frequency band 0 to 80 Hz As a result of calculation, the power spectrum values obtained at fixed time intervals are stored in the measured value master file on the floppy disk for the set number of units, by channel and frequency band. I will write it separately.

Based on the amplitude value (potential) of this power spectrum, a rehabilitation spectrum graph, potential list, potential distribution diagram, and potential fluctuation graph are created a set number of times at regular intervals.

FIG. 2 shows a power spectrum graph of 16 channels. In Figure 2, the vertical axis shows the power, and the horizontal axis shows the frequency from 0 to 80 Hz (based on the amplitude value of the power spectrum calculation result).
Create a power spectrum graph of 16 or 12 channels of 1 scale (511z) and display each frequency band by color for a set number of times.

Further, the amplitude values of the power spectrum are simultaneously created and displayed in a list for a set number of times in each frequency band.

Frequency band classification and frequency band color are delta band (δ) 2.0 to 4.0 Hz
Light blue theta band (θ) 4.0-8.0
Hz Blue alpha 1 band (α1) 8.0-10
．． 0 Hz Pink alpha 2 band (α2) 10
．． 0 to 13.0 Hz Red Figure 3 shows a potential distribution chart for arbitrary frequency bands of 16 channels. Same 3rd
In the figure, since it is not possible to create a potential distribution diagram using only the amplitude values of the electrodes attached to the scalp of channel 16 or 12, other parts are calculated based on a predetermined formula from the surrounding electrode parts. , set the value for the area without electrodes.

The formula for calculating the value of the part without electrodes is A = (1 + 3) ÷ 2 B = (1 + 2) ÷ 2 C = (2 + 4) ÷ 2 D = (1 + 3 + 5 + 12) ÷ 4 (12 CH only)
E= (2+4+6+12)÷4 (12CH only) F= (3+7)÷2 G= (5+6+11+12)÷4 H= (4+8)÷2 ■= (5+7+9+11)÷4 (12CH only) J= (6+8+10+'l 2 )÷4 (12
CH only) K=(7+9)÷2 L=('9+10)÷2 M=(8+10)÷2.

Adding the obtained value of the point without an electrode and the value of the point with an electrode results in 25 points.The lowest value of these 25 points is set as 0%, the highest value as 100%, and this is divided into 11 steps. It is divided into classes and created for a set number of times in each color for each stage and for a set number of times to display an arbitrary frequency band.

Classes for 11 levels and colors are 0 classes 0% Blue 1 class
1-10% Light blue 2 class 11-20%
Light blue/Blue 3 class 21-30% White/Light blue 4
Class 31-40% Yellow/Green 5 class 41
~50% Green/Blue 6 class 51~60%
Green 7 class 61-70% Yellow 8 class 71-80% Peach 9 class 81-90% Purple X class 91-100% Red. An arbitrary band is created and displayed as described above, but when creating and displaying between 6 bands, the highest amplitude value among the 6 bands is set to the X class, and the lowest value is set to the O class.

Next, FIG. 4 shows a graph of potential fluctuations in 6 frequency bands of 16 channels. In Figure 4, the vertical potential (1 scale 1
0μ■), channels are taken on the horizontal axis, power spectrum values of 12 or 16 channels are created at fixed time intervals up to a set number of times, and each frequency band is displayed in different colors.

The display color of each frequency band is Delta band light blue Theta band Blue Alpha] Band Purple Alpha 2 band red Beta 1 band yellow Beta 2 band green It is.

Next, a frequency rhythm graph and a frequency appearance rate graph are created and displayed for a set number of times at fixed time intervals based on the values obtained by calculation by inverse Fourier transform.

FIG. 5 shows a frequency rhythm graph calculated and obtained by inverse Fourier transform of 16 channels.

In Figure 5, the vertical axis is the channel, and the horizontal axis is the time (10
(fixed in seconds), the appearance time of each frequency every 10 seconds of 12 or 16 channels is calculated for a set number of times, and each frequency appearance time is created and displayed in each color for the set number of times every 10 seconds.

The display color of each frequency representing the appearance time is Delta wave light blue Theta waves Blue color Alpha 1 wave purple Alpha 2 wave red Beta 1 wave Yellow Beta 2 wave green It is.

Show. In Figure 6, the vertical axis is the channel, and the horizontal axis is the appearance rate, and the appearance rate of each frequency at each fixed time is expressed as a percentage.The calculation is performed for 12 or 16 channels for the set number of times, and each frequency is calculated for the set number of times at fixed time intervals. Create and display by color.

In addition, the percentage values of the frequency appearance rate are listed at regular intervals,
It can be created and displayed up to a set number of times.

The display color of each frequency that represents the appearance rate is Delta wave light blue Theta waves Blue color Alpha 1 wave purple Alpha 2 wave red Beta 1 wave Yellow Beta 2 wave green It is.

The power spectrum graph, potential-1 table, potential distribution diagram, potential fluctuation graph, frequency rhythm graph, and frequency appearance rate graph can be measured on a floppy disk by specifying the function key on the keyboard, which is the program menu j-number. Load value master file C
The process is to display the information in color on the TR and print it out as a hard copy on the printer.

In this way, brain waves can be continuously displayed in different colors.

(Example) Next, the method for continuously displaying electroencephalograms by color according to the present invention will be specifically explained with reference to an example.

A commercially available personal computer (N
The first test using a device connected to EC PC9801F
Continuous display of electroencephalograms by color was performed using the processing procedure shown in the table.

Table 2 provides an overview of the program's menu numbers.

Table 1 Table 2 Processing procedure QMODE setting When you specify the function key 1 (F・1) on the keyboard, the following items are displayed.

0DE CHANNEL Select 12CH/16CH W
Select AVE 2 /P-P-P-P0PERETION TIME Enter the number of seconds for the fixed calculation time in units of 5 seconds. Setting seconds range: 5 seconds to 60 seconds NO, OF, TIME Set how many times a certain calculation time is to be performed.Input Setting number of times range: 1 time to 60 times INDICATION TIME: Display interval at fixed time intervals AUTO Select 5 second intervals, 10 second intervals .

ND to H Manual display O Examiner data input and registration, frequency band name and frequency band display Keyboard function key 2 (F・2
), the following information will be displayed.

DATE Automatic display TIME Automatic display NUMBER Input within 5 digits NAME Input within 20 digits AGE Input within 2 digits SEX Select f or m and input HAND
Select listener 1 or r Input 0PERETION TI
ME /sec The fixed calculation time entered in the MODE setting is automatically displayed. COUNT The fixed number of calculation times entered in the MODIE setting is automatically displayed. The calculation conditions selected in the WAVE MODE setting are automatically displayed. N0TE Enter the examiner's comment. F.R.E.Q.
UENCY-BAND Frequency band name and frequency are displayed O Measurement data import starts and each calculation starts When function key 3 (F/3) on the keyboard is specified, the following items are displayed Analog signals for the number of channels selected in the MODE setting is displayed on the CRT for the set number of times in 10 second increments. At the same time, power spectrum computation and inverse Fourier transform computation are started at fixed time intervals.

In the power spectrum calculation for a certain period of time, analog signals of all channels are taken in for 5 seconds, and then the power spectrum is calculated and added to the previously obtained power spectrum, which is repeated for a certain period of time. This result is set as a fixed calculation time, and this is repeated a set number of times.

The calculation conditions for the constant calculation time, set number of times, and waveform amplitude are the conditions selected in the MODE setting.

Next, inverse Fourier transform is performed on the analog signals of all channels to calculate the appearance time of each frequency every 10 seconds for each channel, and this is repeated a set number of times.

Further, the inverse Fourier transform is used to calculate the appearance rate of each frequency as a percentage over a certain period of time, and this is repeated a set number of times.

When each of the above calculations is completed for the set number of faces, the bell rings three times.

O Power spectrum graph display When you specify the function key 4 (F.4) on the keyboard, the following items are displayed.

C0UNT - The number on the left indicates the number of constant calculation times.

The number on the right shows the number of settings.

The items selected or input in the display MODE settings of OPE TIME/SEC AVE ATE IME UMBER AME GE EX AND ATE and the examiner data input and registration menus are automatically displayed.

Moreover, it is displayed in the same way in each of the other graph displays.

The amplitude value (potential) of the power spectrum calculation result according to the MODE setting is plotted as power on the vertical axis, and frequency 0 to 801 (
z (I scale: 5 Hz), each frequency band of a power spectrum graph is created and displayed in each color for a set number of times at a fixed time interval.

○Display of power spectrum calculation value When you specify the function key 5 (F・5) on the keyboard, the following items are displayed.

The channels are shown in dark blue, and the frequency bands are shown next to them, and the amplitude values (potentials) of the power spectrum calculation results are created and displayed in a list for each frequency band at a set number of times at regular intervals. The unit is microvolt O Circumference M Number Rhythm graph display When you specify the function key 6 (F・6) on the keyboard, the following items are displayed.

With channels vertically and time horizontally, the appearance time of each frequency every 10 seconds is created and displayed for a set number of times in each color.

When you specify the function key 7 (F・7) on the 0 frequency appearance rate graph keyboard, the following information will be displayed.

Vertical channel, ■ 0 to 100% (1 scale: 10%)
A graph is displayed, and the appearance rate of each frequency is created and displayed for a set number of times in each color for a certain period of time.

Also, if you specify 5ELECT2, the appearance rate value will be created and displayed for the set number of times at regular intervals. Unit is percent ○Potential distribution diagram When you specify function key 8 (F・8) on the keyboard, the following items are displayed.

Potential distribution maps for six frequency bands are simultaneously created and displayed for a set number of times at regular intervals, and the highest and lowest potentials for each frequency band are displayed at regular intervals.

Also, by specifying the number of each band of 1 delta band, 2 theta band, 3 alpha 1 band, 4 alpha 2 band, 5 beta 1 band, and 6 beta 2 band with 5ELECT, you can enlarge and display any frequency band. Out.

O potential distribution value, arbitrary, band list When you press the function key 9 (F・9) on the keyboard, the following items are displayed.

Potential distribution creation values for any band of the six frequency bands are created and displayed a set number of times at regular intervals.

If you specify the function key 10 (F・10) on the O potential fluctuation graph keyboard, the following information will be displayed.

A graph of potential fluctuations in six frequency bands is displayed, with the vertical axis representing the potential and the horizontal axis representing the channel. Create and display the determined power spectrum values at fixed time intervals a set number of times. Also, 5ELE
By specifying a frequency band number using CT, any band can be enlarged and displayed.

○Arbitrary graph selection When you specify the function key 11 (F・11) on the keyboard, the following items are displayed.

Create and display any three selected graphs at the same time for a set number of times at regular intervals.

An arbitrary frequency band is selected and displayed for the potential distribution diagram and the potential fluctuation graph.

The selection method is A. Power spectrum graph B. Frequency rhythm graph C. Frequency appearance rate graph D. Potential distribution diagram (1 delta, 2 theta, 3 alpha 1.
4 Alpha 2.5 Heta 1. 6beta2)\E potential fluctuation graph (1delta, 2theta, 3alphae, 4alpha2.5beta1.6beta2), and select the previous three graphs A, BSC, D, and E. Also, for any frequency band of E, enter the band number in parentheses.

0 Examiner Registration List When you specify the function key 12 (F・12) on the keyboard, the following items will be displayed.

The examiner's number registered on the floppy disk,
The names will be displayed in a list.

(Effects of the Invention) As explained above, the method for continuously displaying electroencephalograms by color according to the present invention has the following excellent effects by continuously displaying each graph at arbitrary predetermined time intervals and up to an arbitrary set number of times.

(1) By analyzing brain waves a set number of times at regular intervals and displaying them continuously, the recorded waveforms can be interpreted quantitatively and objectively and brain functions can be easily grasped by reading the recorded waveforms at regular intervals.
can be observed.

(2) Rhythmia of each frequency at fixed time intervals for clinical applications,
It is possible to observe the occurrence rate, potential distribution for each frequency band, and potential fluctuations, and can be applied to diagnosis and treatment.

(3) Since the continuous color-based display method of electroencephalograms of the present invention quantitatively displays frequencies and frequency bands by color, there is no measurement error caused by the measurer as in the conventional method.

(4) EEG waveform interpretation can be understood in a short time and is easy to explain to the general public.

(5) A method of continuously displaying brain waves by color can be automatically performed by a program.

[Brief explanation of drawings]

Fig. 1 is a flowchart showing an example of the flow of measurement data from an electroencephalogram to carry out the color-based continuous display method of electroencephalograms according to the present invention, Fig. 2 is a power spectrum diagram, and Fig. 3 is a potential distribution diagram. , Figure 4 is a potential fluctuation diagram, Figure 5 is a frequency rhythm diagram,
FIG. 6 is a frequency appearance rate diagram.

Claims (1)

[Claims] (1) Calculate the brain wave waveform of each electrode site inputted by the electroencephalograph at arbitrary fixed time intervals, repeat the calculation up to an arbitrary set number of times, and from the calculated values at arbitrary fixed time intervals,
The power spectrum graph, frequency rhythm graph, frequency appearance rate graph, potential distribution graph, and potential fluctuation graph can be created for an arbitrary set number of times, and displayed continuously by color for an arbitrary fixed time up to an arbitrary set number of times. A method for continuously displaying the characteristic brain waves by graphical color.