JPWO2019163375A1 - Biological signal measuring device, electroencephalograph, and control method - Google Patents

Abstract

The biological signal measuring device (10b) includes a first pulse generator (56a) that outputs a first trigger pulse and a first amplifier circuit (52a) that inputs a biological signal detected by a first electrode that comes into contact with the living body. And the first capacitive element (59a) for superimposing the first trigger pulse on the biological signal, which capacitively couples the output terminal of the first pulse generator (56a) and the input terminal of the first amplifier circuit (52a). Be prepared.

Description

The present invention relates to a biological signal measuring device, an electroencephalograph, a control method, and the like.

A biological signal measuring device that measures a subject's brain wave or heart rate as a biological signal is known. As an example of such a biological signal measuring device, Patent Document 1 discloses an evoked waveform calculation device that obtains a evoked waveform by inputting biological information data such as an electroencephalogram, a magnetoencephalogram, and a myoelectric potential.

Japanese Unexamined Patent Publication No. 10-80409

The present invention provides a biological signal measuring device, an electroencephalograph, a control method, and a program capable of superimposing a pulse on a biological signal detected by an electrode in contact with a living body.

The biological signal measuring device according to one aspect of the present invention includes a first pulse generator that outputs a first pulse, a first amplifier circuit into which a biological signal detected by a first electrode in contact with a living body is input, and the above. It is provided with a first capacitive element for superimposing the first pulse on the biological signal, which capacitively couples the output terminal of the first pulse generator and the input terminal of the first amplifier circuit.

The electroencephalograph according to one aspect of the present invention includes the biological signal measuring device and a mounting portion that brings the first electrode into contact with the head of the living body.

The control method according to one aspect of the present invention is a control method of a biological signal measuring device, wherein the biological signal measuring device uses a first pulse generator that outputs a first pulse and a first electrode that comes into contact with the living body. To superimpose the first pulse on the biological signal by capacitively coupling the first amplifier circuit into which the detected biological signal is input, the output terminal of the first pulse generator, and the input terminal of the first amplifier circuit. The control method includes the operation of the first measurement mode in which the switch element is turned off, and the operation of the first measurement mode, which comprises the capacitance element of the above and a switch element connected between the capacitance element and the input terminal of the first amplifier circuit. By turning on the switch element, the operation of the second measurement mode capable of superimposing the first pulse on the biological signal is performed.

The program according to one aspect of the present invention is a program for causing a computer to execute the control method.

The biological signal measuring device, electroencephalograph, control method, and program of the present invention can superimpose a pulse on the biological signal.

FIG. 1 is an external view showing the configuration of the biological signal measurement system according to the embodiment. FIG. 2A is a diagram showing an example of the shape and schematic configuration of a headphone type headset. FIG. 2B is a diagram showing an example of the shape and schematic configuration of a band-type headset. FIG. 3A is a diagram showing a first example of the shape of the contact surface of the electrode in contact with the skin of the subject. FIG. 3B is a diagram showing a second example of the shape of the contact surface of the electrode in contact with the skin of the subject. FIG. 3C is a diagram showing a third example of the shape of the contact surface of the electrode in contact with the skin of the subject. FIG. 3D is a diagram showing a fourth example of the shape of the contact surface of the electrode in contact with the skin of the subject. FIG. 3E is a diagram showing a fifth example of the shape of the contact surface of the electrode in contact with the skin of the subject. FIG. 4 is a block diagram showing the overall configuration of the biological signal measurement system according to the embodiment. FIG. 5 is a functional block diagram showing a detailed configuration of the headset and the information processing device. FIG. 6 is a block diagram showing the hardware configuration of the headset. FIG. 7 is a block diagram showing a hardware configuration of the information processing device. FIG. 8 is a flowchart showing a basic processing flow of the biological signal measurement system according to the embodiment. FIG. 9 is a circuit block diagram showing a detailed configuration of the biological signal measuring device according to the embodiment. FIG. 10 is a diagram showing an example of the circuit configuration of the attenuation circuit. FIG. 11 is a diagram for explaining a usage example of the first trigger pulse. FIG. 12 is a flowchart of an operation example of the biological signal measuring device. FIG. 13 is a diagram showing a detailed configuration of the biological signal processing unit. FIG. 14 is a flowchart showing an example of display operation of the biological signal measurement system according to the embodiment. FIG. 15 is a diagram showing a display example in the presentation unit in the second measurement mode. FIG. 16 is a diagram showing a display example in the presentation unit in the first measurement mode. FIG. 17 is a circuit block diagram showing a detailed configuration of the biological signal measuring device according to the modified example of the embodiment. FIG. 18A is a first schematic view showing the appearance of the active electrode. FIG. 18B is a second schematic view showing the appearance of the active electrode.

Hereinafter, embodiments will be specifically described with reference to the drawings. It should be noted that all of the embodiments described below show comprehensive or specific examples. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps, order of steps, etc. shown in the following embodiments are examples, and are not intended to limit the present invention. Further, among the components in the following embodiments, the components not described in the independent claims indicating the highest level concept are described as arbitrary components.

It should be noted that each figure is a schematic view and is not necessarily exactly illustrated. Further, in each figure, substantially the same configuration may be designated by the same reference numerals, and duplicate description may be omitted or simplified.

(Embodiment)
[Overview of biological signal measurement system]
FIG. 1 is an external view showing the configuration of the biological signal measurement system 100 according to the embodiment. In FIG. 1, the subject 5 to be measured is also shown.

The biological signal measurement system 100 is a system for measuring the biological signal of the subject 5, and includes a headset 10, an information processing device 20, and a presentation unit 30. The headset 10, the information processing device 20, and the presentation unit 30 are connected by wired communication or wireless communication, respectively, and transmit and receive information between the devices.

The headset 10 is an example of a device for detecting a biological signal, and has an electroencephalograph configuration described later. A plurality of electrodes 51 (see FIGS. 2A and 2B) are attached to the head of the subject 5. The plurality of electrodes 51 include a measuring electrode 51a for measuring a biological signal and a reference electrode 51b for measuring a reference potential used for calculating the difference between the potential measured by the measuring electrode. Further, the headset 10 is provided with an operation input device 10a (see FIG. 5) in which the subject 5 inputs operation information to the biological signal measurement system 100, and an operation for realizing a desired process is input. The biological signal detection device constituting the biological signal measurement system 100 is not limited to the electroencephalograph, but is an electrocardiogram (ECG) signal that detects an electrocardiogram (ECG) signal from electrodes attached to the body, hands, feet, etc. It may be.

The information processing device 20 receives the operation input from the headset 10 and executes a predetermined process. For example, the information processing device 20 may be a computer. The term "predetermined processing" as used herein is a general term for applications such as games, health management, learning, etc. that are performed on a home computer.

The presentation unit 30 is an output device that presents the processing result performed by the information processing device 20. The term "presenting" as used herein includes both displaying an image on a display and / or outputting audio from a speaker. That is, the presentation unit 30 is a display and / or a speaker that displays image information or outputs acoustic information.

[Headset configuration]
2A and 2B are diagrams showing an example of the shape and schematic configuration of the headset 10. FIG. 2A shows a headphone type headset, and FIG. 2B shows a band type headset. Subject 5 wears the headset 10 shown in FIGS. 2A and 2B on his head.

The headset 10 shown in FIG. 2A has an arched headphone shape along the head of the subject 5. The headset 10 shown in FIG. 2A includes a plurality of electrodes 51, a mounting portion 40, and earmuffs 46, as shown.

The mounting portion 40 is an arch-shaped member provided with a plurality of electrodes 51, which is mounted on the head of the subject 5. The mounting portion 40 includes an operation surface 43, an outer surface 44, and a mounting surface 45. The outer side surface 44 is a surface arranged on the side opposite to the head of the subject 5 when the subject 5 wears the headset 10. The mounting surface 45 is a surface that is arranged on the head side of the subject 5 when the subject 5 wears the headset 10. The operation surface 43 has an operation button 41 and a display unit 47. The plurality of electrodes 51 are provided on the mounting surface 45 of the headset 10 and the end of the earmuffs 46 on the same side as the mounting surface 45 of the headset 10.

Before wearing the headset 10, the subject 5 operates the operation button 41 arranged on the operation surface 43 to activate the headset 10, and then wears the headset 10 on the head. In the headset 10, for example, the left earmuff 46 facing the paper in FIG. 2A is located in the right ear of the subject 5, and the right earmuff 46 facing the paper in FIG. 2A is located in the left ear of the subject 5. It is attached to the head of the subject 5. Further, the earmuffs 46 are applied so as to cover the left and right ears of the subject 5. The electrode 51 provided on the mounting surface 45 is applied to the skin (that is, the scalp) of the subject 5. The electrode 51 provided at the end of the earmuffs 46 is applied behind the ear of the subject 5. The electrode 51 provided at the end of the left earmuff 46 facing the paper surface of FIG. 2A is a ground electrode described later, and the electrode 51 provided at the end of the right earmuff 46 facing the paper surface of FIG. 2A will be described later. The reference electrode may be used as a reference electrode, and the other electrode 51 may be a measurement electrode. The arrangement position of the ground electrode and the reference electrode is not limited to this, and the electrode 51 provided at the end of the ear pad 46 on the right side of the paper surface of FIG. 2A is used as the ground electrode, and is left when facing the paper surface of FIG. 2A. The electrode 51 provided at the end of the ear pad 46 may be used as a reference electrode.

The operation surface 43 displays the operation status, the processing result of the application, and the like on the display unit 47.

The headset 10 shown in FIG. 2B has a band-shaped shape that is wrapped around the head of the subject 5 and worn. The band-type headset 10 includes a plurality of electrodes 51 and a mounting portion 40. The mounting portion 40 is an annular member provided with a plurality of electrodes 51, which is mounted on the head of the subject 5. The mounting portion 40 includes an operation surface 43, an outer surface 44, and a mounting surface 45. The configuration of the electrode 51 and the operation surface 43 is the same as that of the headphone type headset 10 shown in FIG. 2A.

Before wearing the headset 10, the subject 5 operates the operation button 41 arranged on the operation surface 43 to activate the headset 10, and then half of the outer surface 44 of the band-type headset 10 (operation). Wear it so that the side of the surface 43) comes to the forehead of the subject 5. The electrode 51 is arranged on the mounting surface 45 and comes into contact with the forehead of the subject 5. Of the plurality of electrodes 51, the electrode 51 corresponding to the ground electrode and the electrode 51 corresponding to the reference electrode may have a configuration in which a lead wire (not shown) is extended from the mounting surface 45 and applied to the back of the ear. Good. The operation surface 43 is further provided with a display unit 47, and the display unit 47 can display the operation status and the processing result of the application. The ground electrode is not a ground electrode (an electrode having a ground potential) generally referred to, but an electrode having a potential that becomes a reference potential in the subject 5.

[Electrode shape]
3A to 3E are views showing an example of the shape of the contact surface of the electrode 51 in contact with the skin of the subject 5. The material of the electrode 51 is composed of a conductive substance. An example of the material of the electrode 51 is gold or silver. The preferred material for the electrode 51 is silver-silver chloride (Ag / AgCl). This is because silver-silver chloride has less polarization when in contact with a living body and has a stable polarization voltage.

The shape of the contact surface of the electrode 51 may be a circle (for example, a diameter of 10 mm) shown in FIG. 3A, which is similar to the electrode used for medical purposes, or may be various shapes depending on the application. For example, it may be a triangle as shown in FIG. 3B, or a quadrangle or square as shown in FIG. 3C.

Further, as the electrode 51 arranged on the mounting surface 45 of the headphone type headset 10, as shown in FIG. 3D, the electrode 51 composed of a plurality of cylinders (five in the figure) may be used. According to this configuration, since the electrode 51 is brought into contact with the skin of the subject 5, the hair can be scraped off. The contact surface of each cylinder with the skin may be circular as shown in FIG. 3D, or may have another shape such as an ellipse. Further, the shape of the electrode 51 is not limited to a cylinder, and may be a prism. The number of cylinders or prisms may be five as shown in FIG. 3D, is not limited to five, and may be changed as appropriate. Further, the tips of the individual cylinders shown in FIG. 3D may have a shape with corners (that is, rounded) on the contact surface side with the skin. As a result, the contact area between each cylinder and the skin can be increased.

Further, as shown in FIG. 3E, the shape of the electrode 51 may be an electrode 51 whose contact surface with the skin of the subject 5 is concentric. The electrode 51 having this shape is used in, for example, the earmuffs 46 of the headphone-type headset 10 of FIG. 2A or the band-type headset 10 of FIG. 2B, and is brought into contact with a hairless portion such as the forehead or the back of the ear. .. Since the electrode 51 having the shape shown in FIG. 3E has a lower pressure on the skin than the electrode 51 having the shape shown in FIG. 3D, the burden on the subject 5 is reduced.

[Configuration of biological signal measurement system]
FIG. 4 is a block diagram showing the overall configuration of the biological signal measurement system 100. As described above, the biological signal measurement system 100 includes a headset 10, an information processing device 20, and a presentation unit 30. The headset 10 includes an operation input device 10a and a biological signal measuring device 10b.

The headset 10 receives the operation input of the subject 5 in the operation input device 10a, and measures the biological signal of the subject 5 at the time of operation in the biological signal measuring device 10b. The biological signal measured by the headset 10 is transmitted to the information processing device 20.

The information processing device 20 receives an input from the operation input device 10a or the biological signal measuring device 10b, performs a predetermined process, and outputs the process result to the presentation unit 30. The headset 10 and the information processing device 20 are connected by wireless communication or wired communication.

FIG. 5 is a functional block diagram showing a detailed configuration of the headset 10 and the information processing device 20. Here, a case where the headset 10 and the information processing device 20 are connected by wireless communication will be described as an example.

The operation input device 10a includes an operation input unit 11 and an operation signal output unit 12.

The operation input unit 11 is an input device that acquires operation input information input from the operation buttons 41 (see FIGS. 2A and 2B) and determines the content of the operation. The operation signal output unit 12 is a transmitter that transmits the operation input information acquired by the operation input unit 11 to the information processing device 20. The operation input information acquired by the operation input unit 11 is transmitted from the operation signal output unit 12 to the information processing device 20.

The biological signal measuring device 10b includes an electrode unit 13, a biological signal amplification unit 14, and a biological signal output unit 15.

The electrode portion 13 is composed of a plurality of electrodes 51. As described above, the plurality of electrodes 51 are composed of a measurement electrode and a reference electrode. The plurality of electrodes 51 are arranged, for example, at positions in contact with the skin of the subject 5.

The biological signal amplification unit 14 is an amplifier that amplifies a biological signal corresponding to a potential difference between a plurality of electrodes 51. Specifically, the biological signal amplification unit 14 includes a measurement electrode 51a (see FIG. 6) arranged on the skin of the subject 5 and a reference electrode 51b (see FIG. 6) arranged behind the ear of the subject 5 among the plurality of electrodes 51. The potential difference with (see FIG. 6) is measured, and the measured potential difference is amplified. The amplified potential difference is converted into a digital signal by, for example, an A / D converter (not shown) provided in the biological signal amplification unit 14. The biological signal output unit 15 is a transmitter that transmits the potential difference amplified by the biological signal amplification unit 14 to the information processing device 20. The potential difference of the biological signal converted into a digital value by the biological signal amplification unit 14 is transmitted from the biological signal output unit 15 to the information processing device 20.

If the biological signal amplification unit 14 can measure a biological signal having a potential magnitude equal to or larger than a predetermined value, it is not necessary to amplify the biological signal, and the biological signal amplification unit 14 may only measure the potentials of the plurality of electrodes 51.

The information processing device 20 includes an operation signal acquisition unit 21, a biological signal acquisition unit 22, a biological signal processing unit 23, an application processing unit (application processing unit) 26, a display information output unit 27, and an acoustic information output unit 28.

The information processing device 20 receives the operation input information in the operation signal acquisition unit 21, and receives the biological signal in the biological signal acquisition unit 22, thereby receiving the information from the headset 10.

Biological signals are often not available as information in the original signals that have just been recorded. Therefore, the biological signal processing unit 23 performs a process of extracting meaningful information from the original signal. For example, in the case of electroencephalogram measurement, the biological signal processing unit 23 extracts a signal of a specific frequency (for example, 10 Hz) and calculates the power spectral density (Power Spectral Density) of the signal at the frequency. The biological signal processing unit 23 may be arranged on the headset 10 side instead of the information processing device 20. That is, in the present embodiment, the electronic device may be composed of the headset 10 and the biological signal processing unit 23.

The application processing unit 26 performs the main application processing (application processing) of the information processing device 20. The application processing is realized by receiving a signal input from the headset 10 and performing a predetermined processing. The predetermined processing includes, for example, game progress in the game application, recording / data management / display in the health management application, question / scoring / result display in the learning application, and the like.

The result processed by the application processing unit 26 is output from the application processing unit 26 to the display information output unit 27 and the acoustic information output unit 28. The display information output unit 27 and the acoustic information output unit 28 output a visual or auditory signal to the presentation unit 30 in order to feed back the result processed by the application processing unit 26 to the subject 5.

The presentation unit 30 presents (that is, display and / or audio output) the signals output from the display information output unit 27 and the acoustic information output unit 28. As a result, the signal is presented to the subject 5. The presentation unit 30 is, for example, a television, a display, or a speaker.

[Headset hardware configuration]
FIG. 6 is a block diagram showing a hardware configuration of the headset 10. The headset 10 includes an operation button group 71, a control signal conversion circuit 72, a measurement electrode 51a, a reference electrode 51b, a ground electrode 51c, a differential amplification circuit 74, an A / D converter 75, a transmission circuit 79, a signal processing unit 78, and an antenna. It includes 80 and a battery 81.

Of these, the operation button group 71 and the control signal conversion circuit 72 correspond to the operation input unit 11 shown in FIG. Each button in the operation button group 71 corresponds to the operation button 41. Further, the measurement electrode 51a, the reference electrode 51b, and the ground electrode 51c correspond to the electrode 51 shown in FIGS. 2A and 2B and the electrode portion 13 shown in FIG. The differential amplifier circuit 74 and the A / D converter 75 are included in the biological signal amplification unit 14.

Further, the signal processing unit 78 has a CPU 101, a RAM 102, a program 103, and a ROM 104. Further, the transmission circuit 79 and the antenna 80 function as the biological signal output unit 15 and / or the operation signal output unit 12 shown in FIG. The transmission circuit 79 and the antenna 80 may be referred to as an "output unit" or a "transmitter".

Each of these components is connected to each other by a bus 105, and data can be exchanged with each other. Further, the headset 10 operates using the battery 81 as a power source.

The pressing information of each button related to the operation button group 71 is converted into a control signal for controlling the operation of the headset 10 in the control signal conversion circuit 72, and sent to the CPU 101 via the bus 105.

The measurement electrode 51a, the reference electrode 51b, and the ground electrode 51c are directly connected to the differential amplifier circuit 74, or are connected via a buffer amplifier or the like. These electrodes are installed in place on the headset 10. The potential difference between the measuring electrode 51a and the reference electrode 51b is amplified by the differential amplification circuit 74 and converted from an analog biological signal to a digital biological signal by the A / D converter 75. The potential difference converted into a digital biological signal is sent to the CPU 101 via the bus 105 as a biological signal that can be processed or transmitted.

The CPU 101 executes the program 103 stored in the RAM 102. The program 103 describes a signal processing procedure in the headset 10 as shown in the flowchart of FIG. 8 described later. The headset 10 converts an operation signal and a biological signal into digital signals according to this program 103, and transmits the operation signal and the biological signal from the antenna 80 via the transmission circuit 79. The program 103 may be stored in the ROM 104.

The signal processing unit 78, the control signal conversion circuit 72, the transmission circuit 79, the differential amplifier circuit 74, and the A / D converter 75 include a DSP (Hardware Signal Processor) in which a computer program is incorporated in one semiconductor integrated circuit. It may be realized as hardware. When mounted on one semiconductor integrated circuit, the mounting area is reduced and the power consumption is also reduced.

Further, the differential amplifier circuit 74 and the A / D converter 75 are integrated in one semiconductor integrated circuit, and the signal processing unit 78, the control signal conversion circuit 72, and the transmission circuit 79 are integrated in another semiconductor integrated circuit. One semiconductor integrated circuit may be connected to each other in one package and integrated as a SiP (system in package), and may be realized as hardware such as a DSP incorporating a computer program. By realizing the above two semiconductor integrated circuits by separate manufacturing processes, it is possible to obtain the effect of reducing the cost as compared with the one mounted on one semiconductor integrated circuit.

[Hardware configuration of information processing device]
FIG. 7 is a block diagram showing a hardware configuration of the information processing device 20. The information processing device 20 includes an antenna 83, a receiving circuit 82, a signal processing unit 108, an image control circuit 84, a display information output circuit 85, an acoustic control circuit 86, an acoustic information output circuit 87, and a power supply 88. Among these components, the antenna 83 and the receiving circuit 82 correspond to the biological signal acquisition unit 22 and / or the operation signal acquisition unit 21 shown in FIG. These are sometimes called "receivers".

The signal processing unit 108 includes a CPU 111, a RAM 112, a program 113, and a ROM 114. The signal processing unit 108 corresponds to the biological signal processing unit 23 and / or the application processing unit 26 shown in FIG. The image control circuit 84 and the display information output circuit 85 correspond to the display information output unit 27 shown in FIG. Further, the acoustic control circuit 86 and the acoustic information output circuit 87 correspond to the acoustic information output unit 28 shown in FIG. These are connected to each other by a bus 115, and data can be exchanged with each other. Further, power is supplied to each circuit from the power supply 88.

The operation information and biometric information from the headset 10 are received by the receiving circuit 82 via the antenna 83 and sent to the CPU 111 via the bus 115.

The CPU 111 executes the program 113 stored in the RAM 112. The program 113 describes a signal processing procedure in the information processing apparatus 20 shown in the flowchart of FIG. 8 to be described later. The information processing device 20 converts an operation signal and a biological signal according to this program 113, performs processing for executing a predetermined application, and generates a signal for giving feedback to the subject 5 by image or sound. The program 113 may be stored in the ROM 114.

The image feedback signal generated by the signal processing unit 108 is output from the display information output circuit 85 to the presentation unit 30 via the image control circuit 84. Similarly, the acoustic feedback signal generated by the signal processing unit 108 is output from the acoustic information output circuit 87 via the acoustic control circuit 86.

The signal processing unit 108, the receiving circuit 82, the image control circuit 84, and the acoustic control circuit 86 may be realized as hardware such as a DSP in which a program is incorporated in one semiconductor integrated circuit. The single semiconductor integrated circuit also has the effect of reducing power consumption.

[Operation of biopotential measurement system]
Next, the operation of the biological signal measurement system 100 according to the present embodiment configured as described above will be described.

FIG. 8 is a flowchart showing a basic processing flow of the biological signal measurement system 100. Steps S11 to S14 show processing in the headset 10 (step S10), and steps S21 to S25 show processing in the information processing device 20 (step S20).

First, the processing step S10 in the headset 10 will be described.

<Step S11>
The operation input unit 11 receives the operation input performed by the subject 5. Specifically, it detects which operation button 41 is pressed at the reception timing. An example of the reception timing is when the operation button 41 is pressed. Whether or not the operation button 41 is pressed is detected, for example, by detecting a mechanical change in the button position or a change in the electric signal when the operation button 41 is pressed. Further, the operation input unit 11 detects the type of operation input received by the operation input unit 11 according to the type of the pressed operation button 41 and transmits the type to the operation signal output unit 12.

<Step S12>
The operation signal output unit 12 transmits an operation signal corresponding to the operation input received by the operation input unit 11 to the information processing device 20.

<Step S13>
The biological signal amplification unit 14 measures and amplifies a biological signal corresponding to a potential difference between a plurality of electrodes 51 in the electrode unit 13. For example, among the plurality of electrodes 51 in the electrode portion 13, the potential difference between the measurement electrode 51a and the reference electrode 51b arranged on the right side of the head (the electrode position of C4 in the international 10-20 method) is measured. In addition, the biological signal amplification unit 14 amplifies the measured biological signal. The amplified biological signal is transmitted from the biological signal amplification unit 14 to the biological signal output unit 15.

<Step S14>
Further, the biological signal output unit 15 transmits the transmitted biological signal to the information processing device 20.

In the processing step S10 of the headset 10, steps S11 and S12 and steps S13 and S14 may be performed in parallel, respectively, and the processing of steps S11 to S14 are all performed in the same order as described above. You don't have to do it.

Next, the processing step S20 in the information processing apparatus 20 will be described.

<Step S21>
In the information processing device 20, the operation signal acquisition unit 21 receives the operation signal from the operation signal output unit 12. The operation signal acquisition unit 21 transmits the received operation signal to the application processing unit 26.

<Step S22>
The biological signal acquisition unit 22 receives the biological signal from the biological signal output unit 15. The biological signal acquisition unit 22 transmits the received biological signal to the biological signal processing unit 23.

<Step S23>
The biological signal received by the biological signal acquisition unit 22 is analyzed and processed by the biological signal processing unit 23 to extract meaningful information. For example, a biological signal having a predetermined frequency component is extracted. The predetermined frequency component is, for example, 10 Hz in the case of measurement of an electroencephalogram.

<Step S24>
The application processing unit 26 receives the operation signal from the operation signal acquisition unit 21 and the biological signal from the biological signal processing unit 23, and performs predetermined processing for executing the current application. As described above, the predetermined processing includes, for example, game progress in the game application, recording / data management / display in the health management application, question / scoring / result display in the learning application, and the like.

<Step S25>
In order to feed back the processing result of the application processing unit 26 to the subject 5, the display information output unit 27 outputs the video information to the presentation unit 30, and the acoustic information output unit 28 outputs the acoustic information to the presentation unit 30. As a result, the presentation unit 30 outputs an image and a sound corresponding to the processing result.

In the processing step S20 of the information processing apparatus 20, the processing of steps S22, S23, and S24 may be performed as parallel processing. Further, the application processing unit 26 does not need to perform processing using both the operation signal from the operation signal acquisition unit 21 and the biological signal from the biological signal processing unit 23, and performs processing using only the biological signal. You may. In that case, step S21 for receiving the operation signal may be omitted.

Through the above processing flow, the biological signal measurement system 100 can obtain biological information such as an electroencephalogram or an electrocardiogram from the subject 5.

[Detailed configuration of biological signal measuring device]
Next, the detailed configuration of the biological signal measuring device 10b included in the headset 10 will be described. FIG. 9 is a circuit block diagram showing a detailed configuration of the biological signal measuring device 10b included in the headset 10. FIG. 9 shows the hardware configuration related to the biological signal measuring device 10b among the hardware configurations included in the headset 10.

The biological signal measuring device 10b includes a measuring electrode 51a, a reference electrode 51b, a first amplifier circuit 52a, a second amplifier circuit 52b, a first high-pass filter 53a, a second high-pass filter 53b, a biological signal amplification unit 14, and a biological signal output unit 15. , The first pulse generator 56a, the first capacitance element 59a, the switch element S1, the control unit 60, and the operation button 41.

The first amplifier circuit 52a is an amplifier into which a biological signal detected by a measuring electrode 51a in contact with a living body is input. The measuring electrode 51a is an example of the first electrode. The first amplifier circuit 52a functions as a so-called buffer amplifier and performs impedance conversion. The first amplifier circuit 52a does not perform voltage amplification (voltage amplification factor is 1), but may perform voltage amplification. In the present specification, the term "amplifier circuit" or "amplifier" is not necessarily limited to an amplifier having a voltage amplification factor larger than 1, and also includes an amplifier circuit or an amplifier having a voltage amplification factor of 1 or less. ..

The second amplifier circuit 52b is an amplifier to which a biological signal detected by a reference electrode 51b in contact with a living body is input. The reference electrode 51b is an example of the second electrode. The second amplifier circuit 52b functions as a so-called buffer amplifier and performs impedance conversion. The second amplifier circuit 52b does not perform voltage amplification (voltage amplification factor is 1), but may perform voltage amplification.

The first high-pass filter 53a is a filter that removes unnecessary low-frequency components of the output signal from the first amplifier circuit 52a. The first high-pass filter 53a is, for example, a passive filter having a cutoff frequency of 0.5 Hz.

The second high-pass filter 53b is a filter that removes unnecessary low-frequency components of the output signal from the second amplifier circuit 52b. The second high-pass filter 53b is, for example, a passive filter having a cutoff frequency of 0.5 Hz.

The biological signal amplification unit 14 includes a differential amplifier circuit 74, a low-pass filter 54, and an A / D converter 75.

The differential amplifier circuit 74 is an amplifier that amplifies the difference (that is, the potential difference) between the output signal CH1_in from the first high-pass filter 53a and the output signal Ref_in from the second high-pass filter 53b. In other words, basically, the differential amplifier circuit 74 amplifies the difference between the signal output from the first amplifier circuit 52a and the signal output from the second amplifier circuit 52b. As a result, the differential amplifier circuit 74 outputs a signal obtained by amplifying the potential at the measuring electrode 51a based on the potential at the reference electrode 51b as a biological signal after amplification. The voltage amplification factor of the differential amplifier circuit 74 is, for example, 1200.

The low-pass filter 54 is a filter that removes unnecessary high-frequency components of the output signal from the differential amplifier circuit 74. The low-pass filter 54 is, for example, an active filter having a cutoff frequency of 100 Hz.

The A / D converter 75 is a converter that samples the output signal from the low-pass filter 54 and converts it into a digital signal. For example, it converts it into a 12-bit digital signal by 1 kHz sampling.

As described above, the biological signal output unit 15 is a transmitter that transmits the potential difference amplified by the biological signal amplification unit 14 to the information processing device 20. The potential difference of the biological signal converted into a digital value by the A / D converter 75 of the biological signal amplification unit 14 is transmitted from the biological signal output unit 15 to the information processing device 20.

By the way, the biological signal measuring device 10b can superimpose the first trigger pulse on the biological signal detected by the measuring electrode 51a. Hereinafter, the first pulse generator 56a, the first capacitance element 59a, the switch element S1, and the control unit 60, which are components for superimposing the first trigger pulse, will be described.

The first pulse generator 56a outputs the first trigger pulse. The first trigger pulse is an example of the first pulse. Specifically, the first pulse generator 56a includes a generation circuit 57a and an attenuation circuit 58a.

The generation circuit 57a is an oscillation circuit that generates the original trigger pulse of the first trigger pulse. The trigger pulse is, in other words, an instantaneous pulse. The trigger pulse is, for example, a triangular pulse, but may be a rectangular pulse, and the shape of the trigger pulse is not particularly limited.

The generation circuit 57a changes at least one of the amplitude and pulse width of the original trigger pulse, for example, based on the operation performed on the operation button 41. As a result, at least one of the amplitude and the pulse width of the first trigger pulse output from the first pulse generator 56a is changed. That is, the first pulse generator 56a can change at least one of the amplitude and the pulse width of the first trigger pulse. At least one of the amplitude and the pulse width of the first trigger pulse may be changed based on the operation of the user interface (not shown) provided in the information processing apparatus 20.

The attenuation circuit 58a attenuates the original trigger pulse generated by the generation circuit 57a and outputs the first trigger pulse obtained by the attenuation of the original trigger pulse. FIG. 10 is a diagram showing an example of the circuit configuration of the attenuation circuit 58a.

As shown in FIG. 10, the attenuation circuit 58a is specifically a voltage divider circuit that divides the original trigger pulse by a resistor. The attenuation circuit 58a is provided between the resistors R1 and R2 that divide the original trigger pulse, the capacitor C1 connected between the resistor R1 and the output terminal of the generation circuit 57a, and the resistor R2 and the output terminal of the generation circuit 57a. Includes a capacitor C2 connected to.

The resistance value of the resistor R1 is, for example, 100 kΩ, and the resistance value of the resistor R2 is, for example, 10 Ω. When the amplitude of the original trigger pulse is 100 mVp-p, the amplitude of the first trigger pulse is 10 μVp-p. The capacitance values of the capacitors C1 and C2 are, for example, 47 μF.

The attenuation circuit 58a may be able to change the amount of attenuation of the original trigger pulse. For example, the resistor R1 is a variable resistor, and the attenuation circuit 58a may change the amount of attenuation by the user directly operating the variable resistor. Further, the resistor R1 is a digital potentiometer, and the attenuation amount may be changed based on the control signal output by the control unit 60.

The biological signal is a weak signal, and the trigger pulse output by a general signal generator has an amplitude too large to be superimposed on the biological signal. Therefore, the attenuation circuit 58a becomes useful.

The first pulse generator 56a may be an interface circuit or a terminal that acquires a first trigger pulse from a signal generator provided outside the biological signal measuring device 10b. That is, it is not essential that the first pulse generator 56a includes a generation circuit 57a and an attenuation circuit 58a.

The first capacitive element 59a capacitively couples the output terminal of the first pulse generator 56a and the input terminal of the first amplifier circuit 52a. The first capacitance element 59a is an element for superimposing the first trigger pulse on the biological signal. The capacitance value of the first capacitance element 59a is, for example, 100 pF.

The switch element S1 is connected between the input terminal of the first capacitance element 59a and the first amplifier circuit 52a. The switch element S1 switches whether or not the input terminals of the first capacitance element 59a and the first amplifier circuit 52a are electrically connected according to the control signal CS1 output from the control unit 60. The switch element S1 is, for example, a FET (Field Effect Transistor), but may be another switch element. Although the switch element S1 may be omitted, if the switch element S1 is turned off when the first trigger pulse is not superimposed on the biological signal, the influence of the first pulse generator 56a on the biological signal is reduced. be able to.

The control unit 60 switches the switch element S1 on and off by outputting the control signal CS1. In the following embodiment, the operation mode in which the first trigger pulse cannot be superimposed on the biological signal by turning off the switch element S1 is described as the first measurement mode. Further, the operation mode in which the first trigger pulse can be superimposed on the biological signal by turning on the switch element S1 is described as the second measurement mode. That is, the control unit 60 operates the first measurement mode and the second measurement mode. The control unit 60 is realized by, for example, a microcomputer or a processor, but may be realized by a dedicated circuit.

The first trigger pulse is used, for example, in the measurement of event-related potential (ERP) to indicate the timing at which the stimulus is presented. FIG. 11 is a diagram for explaining a usage example of the first trigger pulse.

Event-related potentials are electrophysiological responses to internal or external stimuli and can be measured by electroencephalograms. The reaction of P300 is a reaction that appears in the electroencephalogram about 300 ms after the stimulus is presented. In the example of FIG. 11, as the reaction of P300, for example, the reaction (a) when a correct judgment is made to the instruction (that is, the presentation of the stimulus) via the presentation unit 30 and it is recognized, and the presentation unit The reaction (b) when the correct judgment is made for the instruction via 30 but it is not recognized is shown in the figure.

For example, when the character "L" is displayed on the presentation unit 30, the left mouse button is clicked, and when the character "R" is displayed on the presentation unit 30, the right mouse button is clicked. Under the rule, it is assumed that the letter "L" is displayed on the presentation unit 30. In this case, the reaction when the subject 5 clicks the left button of the mouse and is presented with "correct answer" is the reaction (a). Further, the reaction (b) is the reaction when the subject 5 is presented with "incorrect answer" even though the left mouse button is clicked.

In the measurement of the P300 response, the user can easily identify the portion of the brain wave waveform corresponding to the P300 response by displaying the stimulus presentation timing together with the EEG waveform.

Therefore, the biological signal measuring device 10b superimposes the first trigger pulse on the biological signal in synchronization with the presentation of the stimulus. As a result, the presentation unit 30 can display the presentation timing of the stimulus together with the biological signal such as an electroencephalogram. In the measurement of the reaction of P300, since there is a time difference of 300 ms between the presentation timing of the stimulus and the reaction of P300 to this, the first trigger pulse has almost no effect on the reaction of P300.

[Operation example of biological signal measuring device]
Next, an operation example of the biological signal measuring device 10b will be described in detail. FIG. 12 is a flowchart of an operation example of the biological signal measuring device.

The control unit 60 first operates in the first measurement mode. The control unit 60 turns off the switch element S1 by outputting, for example, the low-level control signal CS1 (S31).

Next, the control unit 60 determines whether or not a signal instructing the second measurement mode has been acquired (S32). This determination is performed until a signal indicating the second measurement mode is acquired (NO in S32). The signal instructing the second measurement mode is output from the operation button 41 to the control unit 60, for example, when the operation button 41 is operated to instruct the second measurement mode. The signal instructing the second measurement mode may be output to the control unit 60 based on the operation to the user interface (not shown) provided in the information processing device 20.

When the control unit 60 determines that the signal instructing the second measurement mode has been acquired (YES in S32), the control unit 60 operates in the second measurement mode. The control unit 60 turns on the switch element S1 by outputting the high-level control signal CS1 (S33).

Next, the first pulse generator 56a outputs the first trigger pulse (S34). The first pulse generator 56a acquires, for example, a synchronization signal synchronized with the presentation of the above-mentioned stimulus, and outputs the first trigger pulse at a timing determined by the acquired synchronization signal. As a result, the first trigger pulse is superimposed on the biological signal. The first pulse generator 56a may perform such processing based on the control of the control unit 60.

According to the above operation example, the biological signal measuring device 10b can superimpose a pulse on the biological signal.

[Example of display operation of biological signal measurement system]
Next, an example of the display operation of the waveform of the brain wave of the subject 5 in the biological signal measurement system 100 will be described. First, in relation to the description of the display operation example, the detailed configuration of the biological signal processing unit 23 of the information processing device 20 will be described. FIG. 13 is a diagram showing a detailed configuration of the biological signal processing unit 23. As shown in FIG. 13, the biological signal processing unit 23 includes a biological signal waveform adjusting unit 23a and a biological signal analysis unit 23b.

The biological signal waveform adjusting unit 23a adjusts the waveform of the biological signal acquired by the biological signal acquisition unit 22, such as adjusting the amplitude.

The biological signal analysis unit 23b performs software-like filtering on the waveform-adjusted biological signal. For example, the biological signal analysis unit 23b functions as a high-pass filter or a low-pass filter. The cutoff frequency of the filter can be changed as appropriate by the user. Further, the biological signal analysis unit 23b may include a notch filter that blocks only the frequency of the hum noise (50 Hz or 60 Hz). The biological signal analysis unit 23b performs signal processing using these filters and the like, and generates a biopotential waveform displayed by the presentation unit 30 via the display information output unit 27. Further, the biological signal analysis unit 23b may extract a signal of a specific frequency from the waveform-adjusted biological signal and calculate the power spectral density of the signal at the frequency.

Next, an example of the display operation of the biological signal measurement system 100 will be described. FIG. 14 is a flowchart of a display operation example of the biological signal measurement system 100. FIG. 15 is a diagram showing a display example in the presentation unit 30 in the second measurement mode. FIG. 16 is a diagram showing a display example in the presentation unit 30 in the first measurement mode.

First, the application processing unit 26 performs initial processing (S41). As shown in FIGS. 15 and 16, in the initial processing, the application processing unit 26 has the measurement electrode 51a and the reference electrode 51b included in the headset 10 worn by the subject 5 on the electrode illustration unit 30c in the presentation unit 30. Display the position of.

Next, the application processing unit 26 determines whether or not it is in the second measurement mode (S42). When an operation for instructing the second measurement mode is performed on the operation button 41, the application processing unit 26 receives an operation signal acquisition unit for a notification signal transmitted from the headset 10 in response to the operation for instructing the second measurement mode. It is determined whether or not it has been acquired by 21. Further, when the operation for instructing the second measurement mode is performed on the user interface (not shown) provided in the information processing device 20, the application processing unit 26 determines whether or not such an operation has been performed. To do.

When the application processing unit 26 determines that the second measurement mode is set (YES in S42), the application processing unit 26 displays "trigger pulse input in progress" on the measurement information display unit 30a of the presentation unit 30 as shown in FIG. (S43). Further, the application processing unit 26 displays “trigger pulse input: Yes” on the pulse input status display unit 30e in the presentation unit 30.

On the other hand, when the application processing unit 26 determines that it is in the first measurement mode instead of the second measurement mode (NO in S42), as shown in FIG. 16, the measurement information display unit 30a in the presentation unit 30 is displayed with ". "Measuring biological signal" is displayed (S44). Further, the application processing unit 26 displays “trigger pulse input: none” on the pulse input state display unit 30e in the presentation unit 30.

Then, the biological signal (here, the brain wave signal) is measured by the biological signal measuring device 10b (S45), and the obtained biological signal is transmitted to the biological signal processing unit 23 via the biological signal acquisition unit 22.

In the biological signal processing unit 23 that has acquired the biological signal, the biological signal waveform adjusting unit 23a adjusts the waveform of the biological signal (S46), and the biological signal analysis unit 23b filters the waveform-adjusted biological signal into a signal such as filtering. Perform processing. As a result, the biological signal waveform is output from the biological signal analysis unit 23b to the application processing unit 26.

The application processing unit 26 that has received the biological signal waveform displays the received biological signal waveform on the biological signal waveform display unit 30b of the presentation unit 30 as shown in FIGS. 15 and 16 (S47). Further, as shown in FIG. 15, in the second measurement mode, the application processing unit 26 detects the rise of the trigger pulse and displays an arrow or the like indicating the position of the first trigger pulse on the pulse position display unit 30d.

The biological signal waveform displayed on the biological signal waveform display unit 30b is, for example, an addition and average of a plurality of biological signal waveforms corresponding to a plurality of measurements. In this addition averaging, for example, a plurality of biological signal waveforms are added with reference to the position of the first trigger pulse.

As described above, in the biological signal measurement system 100, the presentation unit 30 shows the measurement information display unit 30a showing the measurement information in real time, the biological signal waveform display unit 30b showing the biological signal waveform, and the electrodes showing the positions of the electrodes. The part 30c and the pulse input state display unit 30e indicating the input state of the trigger pulse are displayed, and a lot of information can be understood at a glance. Further, in the second measurement mode, the pulse position display unit 30d is displayed on the presentation unit 30, and the position of the trigger pulse can be known at a glance.

[Modification example]
In the above embodiment, the measurement electrode 51a for measuring the potential of the biological signal is exemplified as the first electrode, and the first trigger pulse is superimposed on the biological signal detected by the measurement electrode 51a. However, the first electrode may be a reference electrode 51b for measuring the reference potential of the biological signal, or the first trigger pulse may be superimposed on the biological signal detected by the reference electrode 51b.

Further, the trigger pulse may be superimposed on both the biological signal detected by the measuring electrode 51a and the biological signal detected by the reference electrode 51b. FIG. 17 is a circuit block diagram showing a detailed configuration of the biological signal measuring device according to such a modified example.

As shown in FIG. 17, the biological signal measuring device 10c has a second pulse generator 56b, a second capacitance element 59b, and a switch element as components for superimposing the second trigger pulse on the biological signal measuring device 10b. S2 has an added configuration.

The second pulse generator 56b outputs a second trigger pulse. The second trigger pulse is an example of the second pulse. Specifically, the second pulse generator 56b includes a generation circuit 57b and an attenuation circuit 58b.

The generation circuit 57b is an oscillation circuit that generates the original trigger pulse of the second trigger pulse. The generation circuit 57b changes at least one of the amplitude and pulse width of the original trigger pulse, for example, based on the operation performed on the operation button 41. As a result, at least one of the amplitude and the pulse width of the second trigger pulse output from the second pulse generator 56b is changed. That is, the second pulse generator 56b can change at least one of the amplitude and the pulse width of the second trigger pulse. At least one of the amplitude and the pulse width of the second trigger pulse may be changed based on the operation of the user interface (not shown) provided in the information processing apparatus 20.

The attenuation circuit 58b attenuates the original trigger pulse generated by the generation circuit 57b and outputs a second trigger pulse obtained by attenuating the original trigger pulse. The circuit configuration of the attenuation circuit 58b is the same as that of the attenuation circuit 58a.

The second pulse generator 56b may be an interface circuit or a terminal that acquires a second trigger pulse from a signal generator provided outside the biological signal measuring device 10c. That is, it is not essential that the second pulse generator 56b includes a generation circuit 57b and an attenuation circuit 58b.

Further, when the second trigger pulse has the same polarity as the first trigger pulse, the first trigger pulse and the second trigger pulse may cancel each other out in the differential amplifier circuit 74. Therefore, the second trigger pulse may have the opposite polarity to the first trigger pulse.

The second capacitive element 59b capacitively couples the output terminal of the second pulse generator 56b and the input terminal of the second amplifier circuit 52b. The second capacitance element 59b is an element for superimposing the second trigger pulse on the biological signal. The capacitance value of the second capacitance element 59b is, for example, 100 pF.

The switch element S2 is connected between the input terminal of the second capacitance element 59b and the second amplifier circuit 52b. The switch element S2 switches whether or not the input terminals of the second capacitance element 59b and the second amplifier circuit 52b are electrically connected according to the control signal CS2 output from the control unit 60. The switch element S2 is, for example, an FET, but may be another switch element. Although the switch element S2 may be omitted, if the switch element S2 is turned off when the second trigger pulse is not superimposed on the biological signal, the influence of the second pulse generator 56b on the biological signal is reduced. be able to.

The control unit 60 switches the switch element S1 on and off by outputting the control signal CS1, and switches the switch element S2 on and off by outputting the control signal CS2. For example, in the first measurement mode, the switch element S1 and the switch element S2 are turned off, and in the second measurement mode, the switch element S1 and the switch element S2 are turned on.

[Active electrode]
As shown in FIGS. 18A and 18B, the measurement electrode 51a and the first amplifier circuit 52a may be realized as the active electrode 50 by being mounted on one substrate 55, for example. 18A and 18B are schematic views showing the appearance of the active electrode 50. As shown in FIG. 18A, the measuring electrode 51a is mounted on one main surface 55a of the substrate 55, and as shown in FIG. 18B, the first amplifier circuit 52a is mounted on the other main surface 55b of the substrate 55. Will be done. If the measurement electrode 51a and the first amplifier circuit 52a are mounted on one substrate 55 in this way, the wiring length of the wiring that electrically connects the measurement electrode 51a and the first amplifier circuit 52a can be shortened. Then, the generation of unnecessary noise is suppressed.

The first capacitance element 59a and the switch element S1 may be further mounted on the substrate 55. Further, although not shown, the reference electrode 51b and the second amplifier circuit 52b may also be realized as active electrodes by being mounted on one substrate.

[Effects, etc.]
As described above, the biological signal measuring device 10b is a first amplifier circuit 52a in which a first pulse generator 56a for outputting a first trigger pulse and a biological signal detected by a first electrode in contact with a living body are input. And a first capacitive element 59a for superimposing the first trigger pulse on the biological signal, which capacitively couples the output terminal of the first pulse generator 56a and the input terminal of the first amplifier circuit 52a. The first trigger pulse is an example of the first pulse.

Such a biological signal measuring device 10b can superimpose a first trigger pulse on the biological signal.

Further, for example, the first pulse generator 56a includes an attenuation circuit 58a, and the first trigger pulse is a signal in which the original pulse is attenuated by the attenuation circuit 58a.

Such a biological signal measuring device 10b can attenuate a trigger pulse having a relatively large amplitude to generate a first trigger pulse having a relatively small amplitude suitable for a biological signal.

Further, for example, the attenuation circuit 58a can change the attenuation amount of the original pulse.

Such a biological signal measuring device 10b can attenuate a trigger pulse having a relatively large amplitude to generate a first trigger pulse having an arbitrary amplitude suitable for the biological signal.

Further, for example, the first pulse generator 56a can change at least one of the amplitude and the pulse width of the first trigger pulse.

Such a biological signal measuring device 10b can change at least one of the amplitude and the pulse width of the first trigger pulse.

Further, for example, the biological signal measuring device 10b further includes a switch element S1 for switching whether or not the input terminals of the first capacitance element 59a and the first amplifier circuit 52a are electrically connected.

In such a biological signal measuring device 10b, if the switch element S1 is turned off when the first trigger pulse is not superimposed on the biological signal, the influence of the first pulse generator 56a on the biological signal can be reduced.

Further, for example, the biological signal measuring device 10b can further superimpose the first trigger pulse on the biological signal by operating the first measurement mode in which the switch element S1 is turned off and by turning on the switch element S1. A control unit 60 that operates in the second measurement mode is provided.

Such a biological signal measuring device 10b can switch between a first measurement mode and a second measurement mode.

Further, for example, the first electrode is a measurement electrode 51a for measuring the potential of a biological signal.

Such a biological signal measuring device 10b can superimpose the first trigger pulse on the biological signal detected by the measuring electrode 51a. That is, the first trigger pulse can be selectively generated only in the biological signal waveform of the biological signal detected by the specific measuring electrode 51a among the plurality of electrodes 51.

Further, for example, the first electrode is a reference electrode 51b for measuring the reference potential of the biological signal.

Such a biological signal measuring device 10b can superimpose the first trigger pulse on the biological signal detected by the reference electrode 51b. When the first trigger pulse is superimposed on the biological signal detected by the reference electrode 51b, the first trigger pulse appears in common with the biological signal waveform of the biological signal detected by the plurality of electrodes 51 other than the reference electrode 51b. be able to.

Further, for example, the biological signal measuring device 10c further receives a second pulse generator 56b that outputs a second trigger pulse and a second amplifier circuit 52b that receives a biological signal detected by a second electrode in contact with the living body. And a second capacitive element 59b that capacitively couples the output terminal of the second pulse generator 56b and the input terminal of the second amplifier circuit 52b. The second electrode is a reference electrode 51b for measuring the reference potential of the biological signal. The second trigger pulse is an example of the second pulse.

Such a biological signal measuring device 10b can superimpose a second trigger pulse on the biological signal detected by the reference electrode 51b.

Further, for example, the second trigger pulse has the opposite polarity to the first trigger pulse.

As a result, the cancellation of the first trigger pulse and the second trigger pulse in the differential amplifier circuit 74 is suppressed.

Further, the biological signal measuring device 10b further includes a first electrode and a substrate 55 on which the first electrode and the first amplifier circuit 52a are mounted.

In such a biological signal measuring device 10b, the generation of unnecessary noise can be suppressed by shortening the wiring length of the wiring for electrically connecting the first electrode and the first amplifier circuit 52a.

Further, an electroencephalograph such as a headset 10 includes a biological signal measuring device 10b (or a biological signal measuring device 10c) and a wearing portion 40 provided with a first electrode, which is mounted on the head of the living body.

Such an electroencephalograph can superimpose a first trigger pulse on a biological signal.

Further, the control method of the biological signal measuring device 10b (or the biological signal measuring device 10c) is to operate the first measurement mode in which the switch element S1 is turned off, and by turning on the switch element S1, the first trigger pulse is set to the living body. The operation of the second measurement mode that can be superimposed on the signal is performed.

Such a control method can switch between the first measurement mode and the second measurement mode.

(Other embodiments)
Although the embodiments have been described above, the present invention is not limited to such embodiments.

For example, in the above embodiment, the pulse is superimposed at the timing of presenting the stimulus to the subject, but the pulse may be superimposed a plurality of times in the measurement of the biological signal. For example, the pulse may be superimposed at each of the measurement start timing, the stimulus presentation timing, and the measurement end timing. In this case, if the pulse shape is different for each timing, the application processing unit can specify the measurement start timing, the stimulus presentation timing, and the measurement end timing by detecting the pulse.

Further, in the above embodiment, the biological signal measuring device is mainly used for measuring the event-related potential, but the application of the biological signal measuring device is not limited to such an application.

Further, the circuit configuration described in the above embodiment is an example, and the present invention is not limited to the above circuit configuration. That is, similarly to the above circuit configuration, the present invention also includes a circuit capable of realizing the characteristic functions of the present invention. For example, in the present invention, an element such as a switch element (transistor), a resistance element, or a capacitive element is connected in series or in parallel to a certain element within a range in which the same function as the above circuit configuration can be realized. included.

Further, in the above embodiment, another processing unit may execute the processing executed by the specific processing unit. Further, the order of the plurality of processes may be changed, or the plurality of processes may be executed in parallel.

Further, in the above-described embodiment, the components such as the control unit may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or a processor reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory.

In addition, components such as a control unit may be realized by hardware. For example, a component such as a control unit may be a circuit (or an integrated circuit). These circuits may form one circuit as a whole, or may be separate circuits from each other. Further, each of these circuits may be a general-purpose circuit or a dedicated circuit.

Also, general or specific embodiments of the present invention may be implemented in recording media such as systems, devices, methods, integrated circuits, computer programs or computer-readable CD-ROMs. Further, it may be realized by any combination of a system, an apparatus, a method, an integrated circuit, a computer program and a recording medium.

For example, the present invention may be realized as a control method of a biological signal measuring device, or may be realized as a program for causing a computer to execute such a control method. Further, the present invention may be realized as a computer-readable non-temporary recording medium in which such a program is recorded.

Further, the biological signal measurement system described in the above embodiment may be realized as a single device or may be realized by a plurality of devices. When the biological signal measurement system is realized by a plurality of devices, the components included in the biological signal measurement system described in the above embodiment may be distributed to the plurality of devices in any way.

Further, as long as the gist of the present invention is not deviated, one or a plurality of embodiments may be obtained by subjecting the present embodiment to various modifications that can be conceived by those skilled in the art, or by combining components in different embodiments. It may be included in the range of.

10 headset (electroencephalograph)
10b, 10c Biological signal measuring device 40 Mounting part 51a Measuring electrode (first electrode)
51b Reference electrode (first electrode, second electrode)
52a First amplifier circuit 52b Second amplifier circuit 55 Board 56a First pulse generator 56b Second pulse generator 58a, 58b Attenuation circuit 59a First capacitance element 59b Second capacitance element 60 Control unit 74 Differential amplifier circuit S1, S2 Switch element

Claims (14)

The first pulse generator that outputs the first pulse and
The first amplifier circuit to which the biological signal detected by the first electrode in contact with the living body is input,
A biological signal measuring device including a first capacitive element for capacitively coupling the output terminal of the first pulse generator and the input terminal of the first amplifier circuit and superimposing the first pulse on the biological signal. The first pulse generator includes an attenuation circuit.
The biological signal measuring device according to claim 1, wherein the first pulse is a signal in which the original pulse is attenuated by the attenuation circuit. The biological signal measuring device according to claim 2, wherein the attenuation circuit can change the attenuation amount of the original pulse. The biological signal measuring device according to any one of claims 1 to 3, wherein the first pulse generator can change at least one of the amplitude and the pulse width of the first pulse. The biological signal measuring device according to any one of claims 1 to 4, further comprising a switch element for switching the presence or absence of electrical connection between the first capacitance element and the input terminal of the first amplifier circuit. Further, control for operating the first measurement mode in which the switch element is turned off and the operation in the second measurement mode in which the first pulse can be superimposed on the biological signal by turning on the switch element. The biological signal measuring device according to claim 5, further comprising a unit. The biological signal measuring device according to any one of claims 1 to 6, wherein the first electrode is a measuring electrode for measuring the potential of the biological signal. The biological signal measuring device according to any one of claims 1 to 6, wherein the first electrode is a reference electrode for measuring the reference potential of the biological signal. further,
A second pulse generator that outputs the second pulse,
A second amplifier circuit to which a biological signal detected by the second electrode in contact with the living body is input, and
It is provided with a second capacitive element that capacitively couples the output terminal of the second pulse generator and the input terminal of the second amplifier circuit.
The biological signal measuring device according to claim 7, wherein the second electrode is a reference electrode for measuring the reference potential of the biological signal. The biological signal measuring device according to claim 9, wherein the second pulse has the opposite polarity to the first pulse. further,
With the first electrode
The biological signal measuring device according to any one of claims 1 to 10, further comprising the first electrode and a substrate on which the first amplifier circuit is mounted. The biological signal measuring device according to any one of claims 1 to 11.
An electroencephalograph provided with a mounting portion provided with the first electrode, which is mounted on the head of the living body. It is a control method for biological signal measuring devices.
The biological signal measuring device is
The first pulse generator that outputs the first pulse and
The first amplifier circuit to which the biological signal detected by the first electrode in contact with the living body is input,
Capacitive elements for superimposing the first pulse on the biological signal, which capacitively couple the output terminal of the first pulse generator and the input terminal of the first amplifier circuit.
A switch element connected between the capacitance element and the input terminal of the first amplifier circuit is provided.
The control method is
A control method for operating a first measurement mode in which the switch element is turned off, and an operation in a second measurement mode in which the first pulse can be superimposed on the biological signal by turning on the switch element. A program for causing a computer to execute the control method according to claim 13.

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