JP2705602B2 - Brain equipotential diagram creation device and brain equipotential conversion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brain equipotential diagram creating apparatus for creating a brain equipotential map by measuring the surface potential of the scalp, and a brain equipotential conversion for converting the density of grid points corresponding to each measured potential. The present invention relates to a device, and particularly to a brain equipotential diagram creating device and a brain equipotential converting device suitable for examining brain activity with various numbers of electrodes.

[0002]

2. Description of the Related Art Brain equipotential maps (topography mapping)
Is obtained by measuring the potential change caused by activity in the brain as the surface potential on the scalp of the subject and interpolating this as necessary, not only the state of the potential at the position of each electrode but also By computer processing, the whole brain activity can be visually grasped.

[0003] Further, as shown in "Topographic display device of biological signal" disclosed in Japanese Patent Application No. 2-338328, a power spectrum divided by a frequency band from a measured brain potential and specified. These can be displayed by separating the waveforms for observing the waveforms or calculating the equivalent amplitude for checking where the same potential exists.

[0004] When examining the approximate activity of the brain with a brain equipotential diagram, it is better that the number of electrodes attached to the scalp is relatively small, so that the activity of details can be examined or the activity of a deep part of the brain away from the scalp can be examined. When investigating, the number of these electrodes should be relatively large. Therefore, when examining various activities of the brain, the number of electrodes is conventionally changed according to the content to be examined.

[0005] By the way, for example, the upper half area of the head is regarded as a plane, electrodes are arranged in a 9 × 9 grid, and then the electrodes are rearranged in the same area into a 5 × 5 grid arrangement. Assumed to be performed. Such a rearrangement is possible in principle by appropriately thinning out the electrodes. Conversely, for example, when the electrodes are arranged in a 5 × 5 grid, if the electrodes are appropriately added between these electrodes, the electrodes can be arranged with a denser grid such as 9 × 9. . However, each of the electrodes attached to the scalp is provided with a code, and the electrodes are arranged in such a manner that these codes are entangled in a relatively narrow area of the head. Therefore, it is practically impossible to change the density of grid points or the total number of grid points in an electrode arrangement by thinning or adding electrodes.

Therefore, conventionally, when changing the number of electrodes, that is, the number or density of the measurement points at which the electrodes are arranged, all the electrodes which are currently attached are once removed, and the configuration is changed to a new measurement point. Had to be reattached. Then, the brain equipotential map is created in a state where the electrodes are reattached.

[0007]

As described above, conventionally, when the arrangement density of the electrodes is changed from the necessity of creating a brain equipotential diagram according to the situation, all the electrodes are removed from the head and a new electrode is added. Such things as reattachment were being done. For this reason, when converting from the arrangement density or the number of arrangements of a certain electrode to the next arrangement density or the number of arrangements, a certain period of time elapses, and the activity of the brain also changes during this time. For this reason, there is a problem in that even if an attempt is made to compare and analyze these brain equipotential diagrams having different arrangement densities, accurate comparison cannot be performed.

Further, since the electrodes are once removed from the head and mounted again, some of the electrodes will be mounted again at the same position depending on the arrangement density of the electrodes to be changed (density of lattice points). For example, when changing from a 9 × 9 grid electrode group to a 5 × 5 grid electrode group,
Since the number of electrodes to be arranged is only one in two, all of them correspond to the positions where the original electrodes are arranged. However, since the electrodes have to be reattached again due to the circumstances already described, the positions of these electrodes will be slightly different from the previous positions. Therefore, even in this sense, an accurate comparison cannot be performed even if an analysis is performed by comparing brain equipotential diagrams having different lattice point densities.

Conventionally, even if an electrode is to be arranged on the head at a position corresponding to each grid point of a 9 × 9 grid, for example, since the grid points exist outside the head like the four corners of the grid, Electrodes could not be attached, and it was not possible to obtain potential information corresponding to all points on these grids, which was an obstacle to creating brain equipotential maps.

Accordingly, an object of the present invention is to obtain a potential corresponding to all grid points of a predetermined grid structure using a predetermined number of electrodes arranged on the head, and to generate a desired brain equipotential map based on the obtained potential. An object of the present invention is to provide a brain equipotential diagram creating device that can be created.

Another object of the present invention is to change the density of grid points at which potentials are measured or the number of measurement channels using the same brain wave data obtained from electrodes placed on the head. An object of the present invention is to provide a brain equipotential conversion device or a brain equipotential diagram creating device using the same.

[0012]

According to the first aspect of the present invention, (a) a large number of electrodes fixed to the scalp, and (b) a predetermined area of the scalp has a larger number of grid points than the number of the large number of electrodes. Multipoint potential storage means prepared for individually storing the potentials at the respective grid points when divided into grids consisting of: (c) grid points and arrangements among the above-mentioned many electrodes (D) measuring potential storage means for assigning each potential measured by one electrode corresponding to the above one-to-one to these grid points one by one and storing them in a multipoint potential storage means; Calculation potential storage means for storing, in the multipoint potential storage means, potentials calculated from the potentials of the electrodes of the surrounding grid points which have already been allocated to each of the plurality of electrodes which have not been allocated by any of the above-mentioned electrodes; ) Many To and a brain equipotential diagram creating means for creating such electrogram brain using the potential of each grid point stored in the potential storage means to the brain equipotential diagram drawing device.

That is, according to the first aspect of the present invention, a multipoint potential storage means for storing measured values of potentials corresponding to respective grid points when a predetermined area of the scalp is divided into a grid is provided.
Of the electrodes fixed on the scalp, those which correspond to the position one-to-one are associated with these potentials and stored therein. For the non-corresponding ones of the grid points, the potentials of the electrodes of surrounding grid points are stored. The value of the potential calculated from is stored. In this way, the grid points larger than the number of electrodes fixed to the scalp and the corresponding potential information are stored in the multipoint potential storage means to prevent a plurality of electrodes from corresponding to one grid.
In addition, for grids without electrodes, the surrounding electrodes
Are calculated from these potentials, and these are used to create a desired brain equipotential map. As described above, since the potential information of the lattice point is obtained by appropriately interpolating the potential of the lattice points, the electrode arrangement of the test subject is simplified based on the information without replacing the electrodes of the subject one by one. Brain equipotential maps can be easily created.

According to the second aspect of the present invention, when (a) a large number of electrodes fixed to the scalp and (b) a predetermined area of the scalp is divided into a grid composed of a larger number of grid points than the large number of electrodes described above. (C) multi-point potential storage means prepared for individually storing the potentials at the locations located at the respective grid points.
Storing respective potentials thus measured to the electrode of the one corresponding to the arrangement on the one-to-one with the grid point of the many electrodes year to multipoint potential storage unit assigned one of these grid points And (d) each of the grid points which have not been allocated by any of the aforementioned plurality of electrodes have already been allocated.
The calculated potential storage means for storing the potential calculated from the potentials of the electrodes at the surrounding grid points in the multipoint potential storage means, and (e) stored in the multipoint potential storage means by the measured potential storage means and the calculated potential storage means. A grid point potential converting means for converting the potential of each grid point into a potential of grid points of different densities in the same scalp region; and (f) a potential of each grid point or a grid point potential stored in the multipoint potential storing means. The brain equipotential map creating device is provided with a brain equipotential map creating unit that creates a brain equipotential map corresponding to the difference in density of each grid point using the potential of each grid point converted by the converting unit.

That is, according to the second aspect of the present invention, as in the first aspect of the present invention, the grid points larger than the number of electrodes fixed to the scalp and the corresponding potential information are stored in the multipoint potential storage means. I am trying to do it. Then, since the potential information of the grid points having the desired density is obtained by using the grid point potential converting means and the brain equipotential map is created, the same information stored in the multipoint potential storing means is used. In addition, various brain equipotential maps can be created without changing electrodes. Therefore, the activity of the brain at the same time can be observed by brain equipotential diagrams of various numbers of channels (the number of measurement electrodes), and further, the subject is not burdened accordingly.

According to the third aspect of the present invention, (a) a large number of electrodes to be fixed to the scalp, and (b) a predetermined region of the scalp are divided into a lattice comprising more lattice points than the large number of electrodes. Multi-point potential storage means prepared to store the potentials at the positions located at the respective grid points at the time; and (c) those corresponding to the grid points of the above-mentioned many electrodes in a one-to-one correspondence with the layout. Potential storage means for allocating each potential measured by the method to these grid points one by one and storing them in a multipoint potential storage means, and (d) allotted by any of the above-mentioned many electrodes among the grid points. The calculated potentials are calculated from the potentials of the grid points already assigned to each of the missing potentials and the results are stored in a multi-point potential storage means, and (e) measured potential storage means and calculated potential storage means. A grid point potential converting means for converting the respective potentials of the grid points of different densities in the same scalp region the potential of each grid point stored in the multi-point potential storage unit I is provided to the brain equipotential converter.

That is, according to the third aspect of the present invention, multipoint potential storing means for storing potentials corresponding to respective grid points when a predetermined area of the scalp is partitioned in a grid shape is prepared, and an electrode fixed to the scalp is provided. Of these, those that correspond in position are associated with these potentials and stored therein, and those that do not correspond among the grid points are stored with potentials calculated from the potentials of surrounding grid points. Then, since the potential of each grid point stored in the multipoint potential storage means is converted by the grid point potential conversion means to the potential of grid points having different densities in the same scalp region, the potential of the brain at the same time point is changed. Activities can be converted to various grid point densities.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the grid point potential converting means converts the potential of each grid point in a direction in which the density of the grid points decreases, and stores the potential at the multipoint potential storing means. Among the stored potentials, the ones at which the grid points before and after the conversion match in terms of layout are characterized in that the potential at the grid points before the conversion is used as it is as the potential at the grid points after the conversion.

That is, since the information of the state where the density of the lattice points is as high as possible is stored in the multipoint potential storing means and the information is converted in the direction of the low density, the accuracy of the converted potential can be kept good. . In addition, as for the electrode in which the electrode is arranged at the same position even after the conversion of the lattice point density, the potential of the electrode before the conversion is adopted, so that it is possible to save the trouble of calculation. In addition, it is possible to prevent the occurrence of an error due to the calculation as much as possible.

According to a fifth aspect of the present invention, in the fourth aspect of the invention, the multipoint potential storing means stores the potential of each grid point for a 9 × 9 grid, and When converting the potential of each grid point of the 5 × 5 grid into the potential of each grid point, the potential of each of the remaining grid points obtained by thinning out the grid points of the 9 × 9 grid one by one in both the vertical and horizontal directions is calculated. It is characterized by the potential at each grid point.

That is, according to the fifth aspect of the present invention, a 9 × 9 grid structure in which electrodes are arranged at a relatively high density on the head is used to store accurate potential information in multipoint potential storage means. When converting to a 5 × 5 grid structure, since the converted grid points all correspond to the grid points before conversion,
The potential before conversion can be used as it is, and a particularly accurate brain equipotential map can be obtained.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments.

FIG. 1 shows an outline of the configuration of a brain equipotential conversion system using a brain equipotential conversion device according to an embodiment of the present invention. The brain equipotential conversion device includes a CPU (central processing unit) 11. The CPU 11 is connected to each unit in the apparatus via a bus 12 such as a data bus. The working memory 13 is a random access memory (RAM) for temporarily storing programs and various data required for measurement control. The disk controller 14 controls the input / output of the magnetic disk 15. The magnetic disk 15 stores a program for controlling the brain equipotential conversion device and other fixed data.

The electrode input circuit 16 converts the detected potentials obtained from the electrodes 18 ₁ , 18 ₂ ,... 18 _N attached in a matrix to the head 17 of the subject to be subjected to the creation of a brain equipotential map. This is a circuit for analog-to-digital conversion, and the signal before conversion is amplified as required. The operation input circuit 21 is connected to a keyboard 23 to which a mouse 22 as a pointing device is connected, from which operation data is input. In this embodiment, the keyboard 23 or the mouse 22 can be used to switch the density of the grid points on which the brain equipotential map is created.

The display control circuit 24 is a circuit for controlling the display of the CRT 25. Depending on the device, display control of another display such as a liquid crystal display may be performed. The printer control device 26 sends print data to a color printer connected to the printer control device 26 to create a brain equipotential map in color.

In such a brain equipotential conversion system, specifically, the following components and circuit devices are used. First, electrodes 18 ₁ , 18 ₂ ,..., 18 _N use silver chloride electroencephalogram electrodes manufactured by NEC Corporation. For the potential measuring unit constituting the electrode input circuit 16, two biological signal amplifying devices 6R12 also manufactured by NEC Sanei Co., Ltd. are used to measure 64 channels. Here, the electrodes 18 ₁ , 18 ₂ ,..., 18 _N are arranged in a 9 × 9 grid, but portions where the electrodes cannot be arranged, such as portions located outside the head, such as the four corners of the grid. , The electrodes are not actually attached to all of the 81 locations, and the electrodes are attached to up to 64 locations. The signal amplified by the biological signal amplifying device 6R12 is subjected to A / D conversion using an A / D converter ADXM-98A manufactured by Canopus.

Each 1 inputted from the electrode input circuit 16
8 _1, 18 _2, data representing the potential of the ...... 18 _N is
The processing is performed by a microcomputer including other components such as the CPU 11 in FIG. As the microcomputer, PC-9821Af manufactured by NEC Corporation is used. N data measured by the electrodes 18 ₁ , 18 ₂ ,... 18 _N are stored in the multipoint potential storage area of the working memory 13. In addition, 81-
N pieces of data are stored in the microcomputer PC-98.
21Af, and stored in the multipoint potential storage area. The CPU 11 selects potentials necessary for the topography mapping based on data input from the keyboard 23 or the mouse 22 and stores these potentials in the small-point potential storage unit as another area of the working memory 13.

CRT for displaying topography mapping
For 25, a PC-KM172 color display manufactured by NEC Corporation is used. In this embodiment, 64-channel topography mapping is performed using electrodes 18 ₁ , 18 ₂ ,..., 18 _N arranged in a 9 × 9 grid.
Channel topography mapping, 16-channel topography mapping, and 21-channel topography mapping can be displayed.

FIG. 2 shows the arrangement of each electrode in a 9 × 9 grid array. In the figure, black circles (•) represent locations where the electrodes 18 are actually disposed, and white circles (•) represent locations where the electrodes 18 are not disposed. The potentials at a total of 17 points A to Q where the electrodes 18 are not arranged can be estimated by using a plurality of surrounding measured potentials as shown by the following equations.

A = (F ₇ + FP ₁ ) / 2 B = (A + FP ₁ ) / 2 = ((F ₇ + FP ₁ ) / 2 + FP ₁ ) / 2 = (F ₇ +3 FP ₁ ) / 4 C = (FP ₁ + FP) _{Z) / 2 D = (FP} Z + FP 2) / 2 E = (F + FP 2) / 2 = ((FP 2 + F 8) / 2 + FP 2) / 2 = (F 8 + 3FP 2) / 4 F = (FP 2 _{+ F 8) / 2 G =} (A + F 7) / 2 = ((F 7 + FP 1) / 2 + F 7) / 2 = (FP 1 + 3F 7) / 4 H = (FPF 1 + FPF 2 + FP Z + F Z) / 4 _{I = (F + F 8)} / 2 = ((FP 2 + F 8) / 2 + F 8) / 2 = (FP 2 + 3F 8) / 4 J = (T 5 + L) / 2 = (T 5 + (T 5 + O 1 ) / 2) / 2 = ( O 1 + 3T 5) / 4 K = (T 6 + Q) / 2 = (T 6 + (T 6 + O 2) / 2) / 2 = (O 2 + 3T 6) / 4 L = (T ₅ + O ₁ ) / 2 M = (O ₁ + L) / 2 = (O ₁ + (T ₅ + O ₁ ) / 2) / 2 = (T ₅ + 3O ₁ ) / 4 N = (O ₁ + O _Z ) / 2 O = ( O _Z + O ₂ ) / 2 P = (O ₂ + Q) / 2 = (O ₂ + (T ₆ + O ₂ ) / 2) / 2 = (T ₆ + 3O ₂ ) / 4 Q = (T ₆ + O ₂ ) / 2

FIG. 3 shows how the 9 × 9 grid points thus obtained are converted into 5 × 5 grid points. Each of 9 × 9 grid points is 1 in the vertical and horizontal directions.
When thinned out one by one, it can be converted into 5 × 5 grid points. That is, 64 measurement points are obtained by the electrodes 18 ₁ , 18 ₂ ,..., 18 _N (N is 64), and 17 points are estimated by the above-described equation to obtain a total of 81 potentials as 9 × 9 grid points. Once obtained, each potential of the 5 × 5 grid points can be obtained by simply selecting the corresponding grid point. The respective potentials of the 5 × 5 grid points thus obtained are stored in the above-mentioned small point potential storage unit.

Conversion for other grid point densities is performed in the same manner. At this time, when the corresponding grid point does not exist in the grid points of the 9 × 9 grid array, these grid points may be estimated using a plurality of surrounding measurement potentials. The potential of each grid point of the grid arrangement having a smaller total number of grid points than these 9 × 9 grid points is similarly stored in the small point potential storage unit.

Based on the channel number selection information input from the mouse 22 or the keyboard 23, the CPU 11 selects one of the potentials stored in the multipoint potential storage area and the small potential storage section of the working memory 13 as described above. Is selected, a process of creating a brain equipotential map is performed based on these, and the result is displayed on the CRT 25 as topography mapping. The display contents are output by the color printer 27 as needed.

FIG. 4 shows the flow of control performed to store data in the multipoint potential storage area at the time when an electrode is arranged on the subject, in the series of control operations described above. The CPU 11 shown in FIG.
8 ₁ , 18 ₂ ,..., 18 _N
Alternatively, when a multipoint potential storage instruction is input from the keyboard 23 (step S101; Y), these electrodes 18 ₁ ,
18 _2, data obtained from ...... 18 _N (potential) of 9 ×
9 (step S10).
2). Then, in this example, since the potentials corresponding to the 17 grid points are not measured, the potentials on the grid points where these electrodes 18 do not exist are calculated by interpolation (step S103). Then, the obtained 9 × 9 potentials are stored in the multipoint potential storage area (step S104), thereby terminating the control at the initial stage (end).

FIG. 5 shows the contents of the control at the stage of selecting the channel for display after the brain potential information of the subject at a certain point is collected as described above. . When the operator selects the number of channels (step S
201; Y), it is checked whether this is 9 × 9, that is, 81 channels (step S20).
2). If it is 81 channels (Y), all the potentials at these lattice points have already been stored in the multipoint potential storage area in the previous step S104. Therefore, these potentials are input from the multipoint potential storage area to calculate the topography mapping (step S203). Then, the topography mapping corresponding to each potential value is displayed on the CRT 25 or printed out by the color printer 27 as needed (step S204).

On the other hand, if the number of requested channels is 9 × 9, that is, a channel other than 81 channels, it is checked whether or not the requested number of channels has already been subjected to display processing. (Step S20
5). This is because, for example, when a request for 8 × 8 or 64 channels is made first, and a topography mapping is performed for the request, and then a request for the same number of channels is made, this is stored in the point potential storage section. All data corresponding to is already stored. Therefore, it is in order not to perform useless work for re-acquiring these data. Therefore, when the topography mapping is required to be displayed repeatedly for some reason on the data obtained by measuring the subject at the same time (step S205; Y), the data is stored in the small point potential storage unit. Calculation for the topography mapping is performed using the already stored data (step S206), and the topography mapping based on the number of channels corresponding to these potential values is displayed (step S204).

If the display of the topography mapping is requested by the number of channels other than the number of processed channels in step S205 (step S205; N), the grid points corresponding to the multipoint potential storage area or the small point potential storage area are displayed. It is checked whether or not the potentials are uniform, and the potentials of the lattice points that are not uniform are calculated by interpolation (step S207). Then, each potential is stored in the small-point potential storage area (step S
208) On the other hand, the potential of each grid point required for the requested channel is read out from this small-point potential storage area, and calculation for topography mapping is performed (step S20).
9) The topography mapping based on the number of channels corresponding to these potential values is displayed (step S204).

In the above control, the multipoint potential is stored first, and then the topography mapping based on the requested channel is displayed. However, for example, the process proceeds from step S104 to step S203, and the process proceeds to step S203. A topography mapping consisting of × 9 grid points may be displayed. In this case, only when another channel is requested, the potential of the required grid point is estimated and control for displaying the topography mapping is performed.

FIG. 6 shows 64 displayed as described above.
9 illustrates an example of channel topography mapping. This is obtained by converting each of the 64 potentials into potentials at 9 × 9 grid points. In this figure, as in the subsequent figures, +0.3 μV and 0 V
And the region of -0.3 [mu] V.

FIG. 7 similarly shows the outline of the topography mapping of 21 channels based on the respective potentials of 9 × 9 grid points.

FIG. 8 similarly shows the outline of 16-channel topography mapping based on the respective potentials of 9 × 9 grid points.

FIG. 9 similarly shows the outline of the topography mapping of 12 channels based on the respective potentials of 9 × 9 grid points.

In the brain equipotential diagram generating apparatus using the brain equipotential conversion apparatus of this embodiment, after storing the respective potentials of the 9 × 9 grid points in the multipoint potential storage area, Based on the instruction, it is converted into 64 channels, 21 channels, etc., and each brain equipotential map is created.
It is not necessary to replace the electrodes of the subject, and it is possible to create brain equipotential maps in various channels in the same situation.

In the embodiment described above, the electrodes are arranged at the respective positions on the scalp corresponding to the respective grid points of the 9 × 9 grid, and the grid points of the other 5 × 5 grids are determined based on the electrodes. Although the case where the brain equipotential conversion is performed is described, the 9 ×
The electrodes may be arranged at positions corresponding to grid points denser than 9, or conversely, the electrodes may be arranged at positions corresponding to grid points coarser than this.

[0045]

As described above, according to the first aspect of the present invention, a multipoint potential storage for storing a measured value of a potential corresponding to each grid point when a predetermined area of the scalp is partitioned in a grid shape. Prepare the means and position the electrode fixed to the scalp
For the one-to-one correspondence, these potentials are stored in association with each other, and for those that do not correspond to the grid points, the potential values calculated from the potentials of the surrounding grid points are stored and fixed to the scalp. The number of grid points larger than the number of electrodes and the corresponding potential information are stored in the multipoint potential storage means. Electrodes each with interpolated using the potential of the thus surrounding the potential of non-existent grid points of the electrode the electrode
Since there is no plurality of grid points, it is possible to better understand the activity of the brain and to simplify the processing for converting the density of the grid points. Further, since various brain equipotential maps are created based on the information stored in the multipoint potential storage means, it is not necessary to replace the electrodes of the subject one by one, so that the burden on the subject can be reduced and the processing time can be reduced. Can be shortened.

According to the second aspect of the invention, the same effect as that of the first aspect of the invention can be obtained. In addition, the potential information of grid points having a desired density can be obtained by using the grid point potential converting means. Therefore, various brain equipotential maps can be created using the same information stored in the multipoint potential storage means without replacing electrodes. Therefore, the activity of the brain at the same time can be observed by brain equipotential diagrams of various numbers of channels (number of measurement electrodes).

Further, according to the third aspect of the present invention, multipoint potential storing means for storing potentials corresponding to respective grid points when a predetermined region of the scalp is divided into a grid is prepared and fixed to the scalp. For the electrode corresponding to the position, these potentials are stored in association with each other, and for the non-corresponding one of the grid points, the potential calculated from the potential of the surrounding grid points is stored. . Then, since the potential of each grid point stored in the multipoint potential storage means is converted by the grid point potential conversion means to the potential of grid points having different densities in the same scalp region, the potential of the brain at the same time point is changed. Activities can be freely converted into information of various grid point densities.

According to the fourth aspect of the present invention, the information of the state where the density of the lattice points is as high as possible is stored in the multipoint potential storing means, and the information is converted in the direction of the low density. Can maintain good accuracy. In addition, as for the electrode in which the electrode is arranged at the same position even after the conversion of the lattice point density, the potential of the electrode before the conversion is adopted, so that it is possible to save the trouble of calculation. In addition, it is possible to prevent the occurrence of an error due to the calculation as much as possible.

Further, according to the fifth aspect of the present invention, a 9 × 9 grid structure in which electrodes are arranged at a relatively high density on the head, and accurate potential information is stored in the multipoint potential storage means. When converting to a 5 × 5 grid structure, the grid points after the conversion correspond to all the grid points before the conversion.
The potential before conversion can be used as it is, and a particularly accurate brain isoelectric map can be obtained.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an outline of a configuration of a brain equipotential conversion system using a brain equipotential conversion device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an arrangement state of each electrode in a 9 × 9 grid array in the embodiment.

FIG. 3 is an explanatory diagram showing how a 9 × 9 grid point is converted into a 5 × 5 grid point in the embodiment.

FIG. 4 is a flow chart showing a flow of control performed to store data in a multipoint potential storage area when an electrode is arranged on a subject.

FIG. 5 is a flowchart showing the contents of control at the stage when channel selection for display is performed after brain potential information is collected.

FIG. 6 is a brain equipotential diagram showing an outline of 64-channel topography mapping according to the present embodiment.

FIG. 7 is a brain equipotential diagram showing an outline of 21-channel topography mapping according to the present embodiment.

FIG. 8 is a brain equipotential diagram showing the outline of 16-channel topography mapping according to the present embodiment.

FIG. 9 is a brain equipotential diagram showing an outline of 12-channel topography mapping according to the present embodiment.

[Explanation of symbols]

11 CPU 13 working memory 15 magnetic disk 16 electrode input circuit 17 subjects the head 18 ₁ ~ 18 _N electrode 21 operation input circuit 22 mouse 23 keyboard 25 CRT 27 color printer

Claims (5)

(57) [Claims] A plurality of electrodes fixed to the scalp, and a potential at a portion located at each grid point when a predetermined region of the scalp is divided into grids having more grid points than the number of the plurality of electrodes. Multi-point potential storage means prepared for individually storing; and potentials measured by one electrode corresponding to the lattice point of the plurality of electrodes in a one-to-one correspondence with the arrangement. Measuring potential storing means for allocating one to each grid point and storing it in a multi-point potential storing means; and surrounding grid points already allocated for each of the grid points not allocated by any of the plurality of electrodes. work and calculating potentials storing means, the brain equipotential diagram using the potential of each grid point stored in the multi-point potential storage means for storing the potential calculated from the potential of the electrode on the multi-point potential storage unit Brain Equipotential diagram drawing apparatus characterized by comprising a brain equipotential diagram generating means for. 2. The method according to claim 1, wherein a plurality of electrodes fixed to the scalp, and a potential at each of the grid points when a predetermined region of the scalp is divided into grids having more grid points than the number of the plurality of electrodes. and the multi-point potential storage means is provided for storing individually, the respective potentials thus measured to the electrode of the one corresponding to the arrangement on the one-to-one with the previous period lattice point of a previous period multiple electrodes thereof Measuring potential storing means for allocating one to each of the grid points and storing it in the multi-point potential storing means; and surrounding grids already allocated for each of the grid points not allocated by any of the plurality of electrodes. A calculated potential storage means for storing the potential calculated from the potential of the point electrode in the multipoint potential storage means, and the multipoint potential storage means by the measured potential storage means and the calculated potential storage means. A grid point potential converting means for converting the potential of each grid point stored in the row into a potential of grid points of different densities in the same scalp region, and a potential of each grid point stored in the multipoint potential storing means or A brain equipotential map creating means for creating a brain equipotential map corresponding to a difference in density of each grid point using the potential of each grid point converted by the grid point potential converting means. Brain equipotential diagram creation device. 3. A plurality of electrodes to be fixed to the scalp, and a potential at a position located at each grid point when a predetermined region of the scalp is divided into grids having more grid points than the number of the plurality of electrodes. A multipoint potential storage means prepared for storing; and potentials measured by one of the plurality of electrodes, which corresponds to the lattice point in a one-to-one correspondence with the lattice point, one for each of these lattice points. A measured potential storage unit that is allocated and stored in a multipoint potential storage unit; and a result obtained by calculating from potentials of grid points already allocated to each of the grid points that are not allocated by any of the plurality of electrodes. Calculated in the multipoint potential storage means, and each grid point stored in the multipoint potential storage means by the measured potential storage means and the calculated potential storage means Brain Equipotential conversion device characterized by comprising a grid point potential converting means for converting the respective potentials of the grid points of different densities the potentials in the same scalp region. 4. The grid point potential conversion means converts the potential of each grid point in a direction in which the density of the grid points decreases, and outputs the grid points before and after conversion among the potentials stored in the multipoint potential storage means. 4. The brain equipotential conversion device according to claim 3, wherein, for the ones whose arrangement coincides with each other, the potential of the grid point before conversion is used as the potential of the grid point after conversion. 5. The multipoint potential storage means stores the potential of each grid point for a 9 × 9 grid, and the grid point potential conversion means converts the potential to each grid point of a 5 × 5 grid. In this case, the potential of each of the remaining grid points obtained by thinning one grid point of the 9 × 9 grid in both the vertical and horizontal directions is set as the potential of each grid point of the 5 × 5 grid. 4
The brain equipotential conversion device according to the above.