JP2014079387A - Brain function measurement apparatus and brain function measurement method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brain function measurement apparatus capable of eliminating the need for large-scaled surgical operation during extended measurement, reducing the burden on a subject and a risk of developing an infection disease, and ensuring long-term stabilized measurement even when a failure occurs in the apparatus.SOLUTION: A plurality of electrode bodies 1 are attached such that the electrode bodies 1 penetrate the skull 102 of a subject 100, tips 12 are brought into contact with brain surfaces, and base parts 13 are exposed to the outside of the skull 102. A supracranial unit 2A, which is integrated with an electric circuit part 22 to communicate signals by radio with an extracorporeal unit 3 disposed outside the subject 100, is provided with contact parts 21 each coming into contact with the base part 13 of each electrode body 1 on the entire under surface thereof, and is fixed to the skull 102 in an easily detachable manner. In the event that leak of a hazardous liquid is caused by a failure of a supracranial unit 2A, the liquid will not reach the brain. When a supracranial unit 2A is exchanged, only a part of the scalp 101 needs to be incised by a simple operation; no complicated operation is needed.

Description

  The present invention relates to a brain function measuring apparatus and a measuring method for collecting brain function related information reflecting various brain activities and brain functions of subjects such as various experimental animals and humans (humans).

  Recent advances in brain science and medical measurement technologies have been remarkable, and various sensing devices and new brain function imaging technologies have been realized to collect information related to brain functions. Devices for measuring brain function-related information are roughly classified into invasive types and non-invasive types. The invasive type involves some kind of surgical operation such as incision of the scalp or skull of a subject in order to bring an electrode or the like into direct contact with the brain. On the other hand, the non-invasive type accesses the brain indirectly from the outside of the subject's head (that is, through the scalp, skull, etc.) and acquires some brain function related information.

  As noninvasive brain function measurement, excellent measurement techniques such as f-MRI (functional magnetic resonance imaging) and optical topography have been developed, and have achieved great results in the field of diagnosis and research. However, it is difficult to improve performance such as resolution and sensitivity because such measurement is limited to indirect measurement. In addition, since measurement is performed by a large non-portable device provided in a medical facility, measurement cannot be performed for a long time on a subject in a normal activity state. Therefore, in order to obtain brain function related information with high accuracy and high resolution, or to acquire brain function related information of a subject in a normal activity state for a certain long period of time, at least the device An invasive brain measurement in which a part of the head is attached to the subject's head is necessary.

  Conventional invasive brain function measuring devices are roughly classified into those that perform brain surface type measurement and those that perform brain insertion type measurement. The latter type of brain insertion device literally has a needle electrode inserted into the brain and can acquire an electrical signal in a relatively deep part of the brain. For example, the so-called device developed at the University of Michigan in the United States Michigan electrodes and so-called Utah electrodes developed at the University of Utah (see Non-Patent Document 1) have been reported for a long time. Such an electrode has a sword mountain-like structure in which needle-like electrodes are arranged at a high density, whereby information in the brain over a certain wide range can be collected. However, since the brain insertion type damages the brain, damage to the brain is great. In addition, since electrode performance deteriorates with time due to an immune reaction of the brain, it is difficult to perform stable measurement over a long period of time.

  On the other hand, as the former brain surface type device, what is called an ECoG electrode is known. For example, there is a unique medical intracranial electrode approved for clinical treatment of epilepsy in Japan (see Non-Patent Document 2). Non-patent document 3 discloses a long-term measurement technique using an ECoG electrode. Such a brain surface type device is inferior in spatial resolution to the brain insertion type, but has little damage to the brain and little deterioration in performance over time. It is also suitable for a wide range of measurements. For these reasons, brain surface type measurement is advantageous for acquiring stable brain function-related information for a relatively long period of time without hindering the free activity of the subject.

  As described above, in order to continue measurement for a relatively long period of time without hindering the free activity of the subject, it is desirable that the connection between the inside and outside of the subject be a wireless system. From this point of view, the inventors of this application disclosed in Patent Document 1 an in-brain information measurement device that wirelessly transmits an electrical signal obtained by an in-body wearing unit in which an electrode inserted into the brain is integrated to an in-vitro measuring unit. Has proposed. In this document, a passive type which does not have an active circuit in the in-vivo mounting portion as a low-cost configuration that is unlikely to fail is proposed. However, in order to perform advanced measurement, an electric circuit such as a CMOS integrated circuit is used. It is necessary to adopt an active configuration built in the body mounting portion. However, if it does so, a failure is likely to occur, and it may be necessary to replace a CMOS integrated circuit or the like in order to improve the function.

  In the configuration described in Patent Document 1, when it is necessary to replace a body-mounted part that has failed or has an old function, it is not necessary to incise the skull, but it is inserted into the through-hole of the skull and inserted into the brain. The inserted electrode must be removed. If it becomes so, it will also give a big burden with respect to a test subject, and the risk of infection etc. will also become high.

International Publication WO2010 / 038393

Craig T. Nordhausen and 2 others, “Optimizing recording capabilities of the Utah Intracortical Electrode Array”, “Intracranial electrode”, [online], Unique Medical Co., Ltd. [searched September 24, 2012], Internet <URL http://www.mmjp.or.jp/unique-medical/newuzncatNo1018b.pdf> “Established Brain Machine Interface (BMI) technology with long-term stability”, RIKEN, April 6, 2010 [Search September 24, 2012], Internet <URL: http: // www.riken.go.jp/r-world/research/results/2010/100406/image/100406.pdf>

  The present invention has been made in view of the above problems, and its main purpose is that it does not require a large surgical operation for mounting, and even when used for a long period of time, the burden on the subject and the risk of infectious diseases are reduced. To provide a brain function measuring device and a measuring method capable of maintaining the device with a few simple operations and collecting stable brain function-related information over a long period of time without disturbing the free activity of a subject. It is in.

The present invention made to achieve the above object is a brain function measuring device for collecting information related to brain functions of subjects including various experimental animals and humans,
a) It is inserted into a through-hole drilled in a skull of a subject or an artificial skull attached to the subject instead of a part of the skull, and a distal end portion is exposed to the inside of the skull or the artificial skull. A plurality of electrodes in contact with a membrane covering the brain, while a base is exposed to the outside of the skull or artificial skull;
b) a contact part that is detachably fixed to the outside of the skull or artificial skull and that is exposed to the outside of the skull or artificial skull; and a contact part that contacts the base part of the plurality of electrodes; A signal relay unit that wirelessly transmits the electrical signal obtained or the electrical signal applied to the electrode via the contact part to the outside of the subject's scalp, or receives from the outside, a skull unit,
c) an extracorporeal unit that is provided outside the scalp of the subject, receives a signal transmitted wirelessly from the signal relay unit of the above-cranial unit, or transmits a signal wirelessly to the signal relay unit;
It is characterized by having.

A brain function measurement method according to the present invention is a brain function measurement method that collects information related to the brain function of a subject including various experimental animals and humans, using the above-described brain function measurement device,
a) A plurality of through holes are drilled in the skull of the subject or an artificial skull to be attached to the subject instead of a part of the skull, and the tip of each through hole is exposed inside the skull or the artificial skull. And the electrode is inserted so that the base is exposed to the outside of the skull or artificial skull while contacting the brain or the membrane covering the brain,
b) Further, contact portions that respectively contact the base portions of the plurality of electrodes that are exposed to the outside of the skull or the artificial skull, and electrical signals obtained from the electrodes via the contact portions or via the contact portions A signal relay unit that wirelessly transmits an electrical signal to be applied to the electrode to the outside of the subject's scalp or receives from the outside, and the contact unit is a base of the plurality of electrodes, respectively. After detachably fixing to the outside of the skull or artificial skull so as to contact,
An electrical signal obtained by the electrode whose tip is in contact with the subject's brain or a membrane covering the brain is transmitted to the signal relay unit of the above-cranial unit via the contact part in contact with the base of the electrode. The brain function-related information is acquired by receiving the signal transmitted wirelessly in the signal relay unit by an extracorporeal unit provided outside the subject's body.

  In the cerebral function measuring device and the measuring method according to the present invention, the tip of the cerebral dura mater and the arachnoid membrane directly contact the brain (however, the cerebral buffy coat attached to the brain surface does not penetrate, Including the case of penetrating into the brain body through the cerebral buffy coat) or the conductive signal that is indirectly in contact with the brain without penetrating the cerebral dura mater and the electrical signal obtained from the electrode wirelessly And the above-mentioned skull unit having a function of transmitting the outside of the subject's scalp or receiving the control signal etc. coming from the outside, completely separate, and the contact unit provided in the above-cranial unit; Each electrical contact is ensured with the base of each electrode.

  A plurality of electrodes typically have a single member made of a conductor such as a substantially elongated metal that does not have an active function, or a conductor as a base, and conductivity between the tip and the base, etc. Other than the required portion, a single member in which the periphery of the base is covered with an insulator and is almost permanently fixed to the skull or the artificial skull. The electrode conductor is preferably a stable metal having corrosion resistance, such as platinum. In addition, the through hole provided in the skull or artificial skull is liquid-sealed with the electrode inserted, that is, the flow of liquid through the gap between the inner wall surface of the through hole and the outer peripheral surface of the electrode is sufficient. It is desirable to be prevented. On the other hand, the supracranial unit including an electric circuit or the like that realizes an active function is disposed outside the skull or artificial skull, is detachable from the skull or artificial skull, and is simply in contact with the electrode. Easy to remove.

  Since the above-the-cranial unit has an electric circuit and the like, it is relatively easy to break down, and if it has a built-in battery, it is necessary to replace the battery (or replace the main body itself). For this reason, it is possible to easily remove or replace the subject by cutting the scalp of the subject. On the other hand, since the electrodes can be used almost semipermanently, even when measuring brain function-related information over a long period of time, it is only necessary to perform a surgical operation incising the scalp of the subject during that period. Surgical operations such as incising or perforating the skull with high burden and high risk of infection can be avoided. As described above, by sufficiently sealing the electrode, even if the above-cranial unit breaks down and a harmful liquid substance leaks out of the unit, such a liquid substance may be present inside the skull or artificial skull. Reaching the brain can be prevented.

  In addition, in the brain function measuring apparatus and the measuring method according to the present invention, it is preferable to be able to perform optical measurements such as optical topography (NIRS measurement), IOS measurement, fluorescence imaging measurement as well as electrical measurement such as brain waves. .

Therefore, the brain function measuring apparatus according to the present invention is preferably inserted into a through-hole drilled in the skull or artificial skull of the subject, and the tip portion of the skull or artificial skull is similar to the plurality of electrodes. A light guide body that is exposed to the inside and contacts the brain or a membrane covering the brain, while a base is exposed to the outside of the skull or artificial skull, further comprising:
The upper skull unit includes an optical coupling unit optically coupled to a base of the light guide exposed outside the skull or the artificial skull, and an optical signal to the brain through the optical coupling unit and the light guide. And a light receiving unit that receives an optical signal obtained through the light guide and the optical coupling unit and converts it into an electrical signal.

  That is, the light guide provided so as to penetrate the skull or artificial skull serves as an optical window between the outside and inside of the skull or artificial skull.For example, for near infrared light irradiated to the brain, Light reflected, scattered or passed near the brain surface can be efficiently captured. Moreover, since light can be irradiated to the brain from a light emitting part such as an LED built in the above-cranial unit through a light guide of a very short distance, strong light stimulation to the brain can be given.

  According to such a configuration, not only electrical information but also optical information can be extracted from the brain. Furthermore, conversely, electrical stimulation can be applied to the brain using the electrodes, or optical stimulation can be applied to the brain through the light guide. By combining this, it is possible to acquire changes in the electroencephalogram when an optical stimulus is applied as electrical information, and conversely, acquire changes in the blood flow when an electrical stimulus is applied as optical information. You can also.

  Further, in the brain function measuring device and the measuring method according to the present invention, when measuring a predetermined range of the brain, it is necessary to dispose electrodes or light guides on the skull or artificial skull with an appropriate density. The contact part and / or the optical coupling part of the unit on the skull are arranged two-dimensionally on one surface of the casing of the unit, and an electrode or a light guide within an appropriate two-dimensional range can be obtained with one unit on the skull. It is recommended to perform the combination.

  The method of fixing the upper skull unit to the skull or artificial skull is not particularly limited as long as it is detachable, but it is troublesome to attach the unit itself using a fixing member such as a screw, and forget to attach the fixing member. There is also a risk of falling off. Therefore, in the brain function measuring device and the measuring method according to the present invention, a concave portion corresponding to the outer shape of the case of the above-cranial unit is formed outside the skull of the subject or the artificial skull attached to the subject, A unit on the skull may be fitted into the recess.

  Specifically, it is preferable to form a recess according to the outer shape of the housing of the upper skull unit by cutting a part of the outer side of the skull or the artificial skull to such an extent that there is no problem in its strength. Or you may fix the frame member which can form the recessed part according to the housing | casing external shape of an upper skull unit in the outer side of the skull of a test subject, or the artificial skull with which this test subject is mounted | worn. In any case, the unit can be attached by fitting the upper skull unit in the recess, and conversely, the unit can be removed by peeling off the upper skull unit fitted in the recess. Therefore, replacement and repair of the skull unit is easy.

  In the brain function measurement method according to the present invention, when it is desired to perform measurement over a wide two-dimensional range of the brain, a plurality of upper skull units are provided outside the skull of the subject or the artificial skull attached to the subject. It is good to fix. In particular, by standardizing the arrangement and pitch of multiple electrodes and light guides attached to the skull or artificial skull in advance, and by standardizing the shape and size of the skull unit accordingly, the number of skull units to be used can be reduced. It can be increased to cope with the expansion of the measurement target range.

According to the brain function measuring device and the measuring method according to the present invention, the following effects can be achieved.
(1) The cranial unit that may need to be replaced or repaired during long-term use is placed outside the skull of the subject or the artificial skull attached to the subject. Since it is a separate body from the electrode penetrating the skull, the supracranial unit can be exchanged or removed by a simple surgical operation. In addition, when attaching electrodes or light guides to the skull of the subject for measurement, it is only necessary to drill holes in the skull so that the elongated electrodes and light guides can penetrate. Compared to a large incision in the skull, a relatively simple surgical operation is sufficient. For this reason, the burden on the subject can be reduced even during a long-term measurement period. Thereby, it is difficult to impair the smoothness of the biological activity of the subject at the time of wearing, and the stability and accuracy of measurement are improved.

  (2) There are no high-risk factors such as electrical wiring or electrical circuits inside the skull of the subject, and such risk factors are arranged outside the skull. In addition, if the electrodes or light guides penetrating the skull or artificial skull are sufficiently sealed, even if the above-the-cranial unit breaks down or is damaged, the direct influence on the brain can be avoided. It is possible to continue measurement by simply replacing the skull unit.

(3) Since signal transmission by radio is performed between the skull unit and the extracorporeal unit, the subject has a high degree of freedom of action, and meaningful measurement under such free action is possible.
(4) In order to expand the measurement range of the brain, the number of electrodes and light guides attached to the skull or artificial skull can be increased, and the number of on-cranial units provided outside can be increased. Therefore, the expandability and flexibility are high.

1 is an external plan view showing a basic configuration of a brain function measuring apparatus according to an embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view showing a state in which the brain function measuring device according to the present embodiment is attached to a subject such as a laboratory animal. The external appearance perspective view which shows the structural example of the electrode body in the brain function measuring apparatus of a present Example. The schematic perspective view at the time of mounting on the skull unit in the brain function measuring apparatus of a present Example. The circuit block block diagram of the unit on the skull in the brain function measuring apparatus of a present Example. The circuit block block diagram of the extracorporeal unit in the brain function measuring apparatus of a present Example. The schematic sectional drawing which shows the other example of the attachment structure of the unit on the skull to the skull. The schematic plan view which shows the structural example in the case of attaching a some skull unit to a skull.

Hereinafter, an embodiment of a brain function measuring device and a measuring method according to the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an external perspective view showing basic components of the brain function measuring apparatus of the present embodiment, and FIG. 2 is a schematic sectional view showing a state in which the brain function measuring apparatus of the present embodiment is mounted on a subject such as a laboratory animal. 3 is an external perspective view showing an example of the structure of the electrode body in FIG. 1, and FIG. 4 is a schematic perspective view when the upper skull unit in FIG. 1 is mounted.

  As shown in FIG. 1 (a), the brain function measuring apparatus according to the present embodiment has a plurality of electrode bodies 1 in which a distal end portion 12 is provided at one end of a shaft portion 11 having an elongated and substantially cylindrical shape, and a base portion 13 is provided at the other end. A plurality of conductive contact portions 21 disposed on one surface of a flat housing, and an upper skull unit 2A in which an electric circuit portion 22 described later is incorporated, and an extracorporeal unit 3 having an arbitrary shape. It is a basic component. As shown in FIG. 1B, a light guide body 4 having a shaft portion 41, a tip portion 42, and a base portion 43 having a shape similar to that of the electrode body 1 may be used. In that case, a plurality of contact portions are used. The above-cranial unit 2B in which a part of 21 is replaced with the optical coupling unit 23 is used.

  Among the above basic components, the electrode body 1 and the light guide 4 are the skull 102 of the subject 100 (or an artificial skull that is replaced with a part of the skull of the subject 100: In the following description, “skull 102”. Is clearly provided so as to penetrate the artificial skull (not described as “artificial skull”), and the upper skull units 2A and 2B are provided between the skull 102 and the scalp 101 of the subject 100. The extracorporeal unit 3 is disposed outside the subject 100, that is, further outside the scalp 101.

  The electrode body 1 is basically made of a conductor such as a metal, preferably a metal which is not easily corroded and is stable over a long period of time, such as platinum. As shown in FIG. 3A, when the distal end portion 12 is inserted into a hole having a slightly larger diameter than the shaft portion 11 (that is, when receiving a load from the outside) as will be described later. It has a structure having a spring property that is recessed inward and expands outward when there is no load from the outside through the hole. However, only the lower part of the tip part 12 and the upper part of the base part 13 need electrical conductivity in the part exposed to the outside. Therefore, as shown in FIG. It is good also as a structure which covered the circumference | surroundings of the conductor with the insulating film 14 except for a certain part. According to such a structure, it becomes difficult to pick up signals other than the target region in the brain, which is advantageous in improving the signal-to-noise ratio of the signal.

  On the other hand, the light guide 4 is made of a material such as quartz glass that can stably obtain high transparency over a long period of time. The light guide 4 may be an optical fiber bundle or the like. Further, the light collection efficiency and the convergence may be enhanced by configuring the tip portion 12 and the base portion 13 to have a lens action.

  As shown in FIG. 2, the electrode body 1 has a shaft portion 11 having a diameter slightly larger than the outer diameter of the shaft portion 11 provided through the skull (or artificial skull) 102 of the subject 100. The distal end 12 is attached to the inside of the skull (or artificial skull) 102, and the base 13 is attached to be exposed to the outside of the skull (or artificial skull) 102. In the example of FIG. 2, the distal end portion 12 penetrates the cerebral dura 103 attached to the inside of the skull 102, and is in contact with the surface of the arachnoid membrane 104 that covers the cerebral cortex (strictly the cerebral puffy coat) 105. However, the distal end portion 12 may contact the surface of the dura mater 103 without penetrating the dura mater 103. Alternatively, the distal end portion 12 may penetrate the arachnoid membrane 104 and the cerebral buffy coat and be inserted into the cerebral cortex 105. The light guide 4 is the same as the electrode 1. Moreover, when attaching the electrode body 1 and the light guide 4 as described above, an artificial dura mater or a dura mater collected from another animal may be used as necessary.

  In FIG. 1 to FIG. 3, the shaft portions 11 and 41 of the electrode body 1 and the light guide body 4 are linearly shaped, so that the portion immediately below the distal end portions 13 and 43 exposed on the skull 102 is a measurement target or Although it is a site to be stimulated, the shaft portions 11 and 41 may be appropriately bent. That is, the shape of the through hole formed in the skull 102 may be a bent shape, and the electrode body 1 and the light guide 4 may be inserted along the shape. In this case, since the portion immediately below the distal end portions 13 and 43 exposed on the skull 102 does not become a site to be measured or stimulated, on the contrary, it is difficult to mount the skull unit 2A or 2B. This is useful when you want to measure or stimulate directly below the upper part.

  In addition, the electrode body 1 and the light guide 4 are not attached to the skull 102 of the subject 100, but are attached to the head of the subject 100 so as to replace a part of the skull 102 of the subject 100. The electrode body 1 and the light guide 4 may be attached to the artificial skull. In this case, before attaching the artificial skull to the head of the subject 100 in advance, a plurality of electrode bodies 1 and light guide bodies 4 are attached to the artificial skull, and the electrode body 1 and light guide body 4 are attached. The artificial skull in a state may be attached to the head of the subject 100 by surgical operation, or a plurality of electrodes may be attached to the artificial skull after the artificial skull is attached to the head of the subject 100 by surgical operation. The body 1 and the light guide 4 may be attached.

  In addition, in a state where the electrode body 1 and the light guide 4 are inserted into the through hole formed in the skull 102, a liquid is provided between the outer peripheral surface of the electrode body 1 and the light guide 4 and the inner peripheral surface of the through hole. A dense state is preferred. Therefore, for example, when the electrode body 1 or the light guide body 4 is inserted, the liquid-tightness may be ensured by a method such as filling a harmless sealant between them. As a result, for example, as will be described later, even if the overhead skull units 2A and 2B break down and harmful liquid leaks from the units 2A and 2B, the gap between the through hole and the electrode body 1 or the light guide 4 is passed. It is possible to prevent the harmful liquid from entering the inside of the skull 102.

  The contact portions 21 of the upper skull units 2A and 2B are provided two-dimensionally corresponding to the positions of the base portions 13 of the plurality of electrode bodies 1 exposed to the outside of the skull 102, and are optically coupled to the upper skull unit 2B. The portion 23 is provided two-dimensionally corresponding to the position of the base portion 43 of the plurality of light guides 4 exposed to the outside of the skull 102. Therefore, as shown in FIG. 4, when the upper skull unit 2A is attached at a predetermined position outside the skull 102 to which the plurality of electrode bodies 1 are attached, each contact portion 21 of the upper skull unit 2A is connected to each electrode body. 1 is in contact with the base 13 and electrical continuity between the two is ensured. Further, when the upper skull unit 2B is attached to a predetermined position outside the skull 102 to which the plurality of electrode bodies 1 and the light guide 4 are attached, each contact portion 21 of the upper skull unit 2B is connected to each electrode body 1. Each of the optical coupling portions 23 is brought into close contact with the base portion 43 of each light guide 4 and is in contact with the base portion 13 to ensure electrical continuity between them. Mutual propagation is ensured.

  In the example of FIG. 2, the holding member 24 is fixed to the outside of the skull 102 with a screw 25, and the units 2 </ b> A and 2 </ b> B can be easily detached by fitting the upper skull units 2 </ b> A and 2 </ b> B into the holding space formed by the holding member 24. It is fixed to. Of course, the method of attaching the skull units 2A and 2B to the skull 102 is not limited to this.

  For example, when the number of the skull units 2A and 2B to be attached is small, as shown in FIG. 7A, the screws inserted into the screw holes of the flange 26 formed integrally with the housings of the units 2A and 2B. The units 2A and 2B may be fixed by screwing 27 into the skull 102.

Alternatively, as shown in FIG. 7 (b), the upper skull units 2A and 2B are fixed by being fitted into a recess (or holding space) 110 formed by cutting a part of the outer surface of the skull 102. Also good. Of course, when cutting a skull or an artificial skull, it is necessary not to greatly impair the strength. In particular, according to the method of fixing the skull or the artificial skull itself, it is not necessary to use a separate member such as a screw, so that not only is it easy to attach and remove, but the screw may fall off in the body of the subject, for example, the scalp. It is possible to prevent the occurrence of work mistakes such as damage or misplacement of screws in the body of the subject.
In any case, it is preferable to adopt an attachment method in which the upper skull units 2A and 2B are stably held on the skull or the artificial skull and can be easily replaced or removed when necessary.

  In the structure in which the planar shape of the casings of the upper skull units 2A and 2B is substantially hexagonal and the upper skull units 2A and 2B are fitted and attached to the recesses 110 formed in the skull 102 as shown in FIG. 7B. When it is desired to attach a plurality of upper skull units 2A and 2B, as shown in FIG. 8, the concave portions 110 are formed in a substantially honeycomb shape, and the upper skull units 2A and 2B are fitted into the concave portions 110, respectively. Good.

FIG. 5 is a schematic block configuration diagram of the electric circuit unit 22 built in the skull unit 2 </ b> B, and FIG. 6 is a schematic block configuration diagram of the electric circuit unit built in the extracorporeal unit 3.
The electrical circuit unit 22 of the skull unit 2B includes a built-in antenna 220, an antenna drive unit 221, a modulation unit 222, a demodulation unit 223, a power supply unit 224, a control unit 225, and a signal processing unit 226. ID storage unit 227, LED 228, and optical sensor 229. Each of the plurality of skull units 2 </ b> B has unique identification information (ID), and the identification information is stored in the ID storage unit 227 in advance.

  In the case of the cranial unit 2A that does not exchange optical stimuli or information with the brain, the LED 228 and the optical sensor 229 are not provided, and the control unit 225 and the signal processing unit 226 control the driving of the LED 228. The only difference is that it does not have functions such as processing of the received light signal, and the other points are the same as those of the upper skull unit 2B. Accordingly, much of the following description is applicable to the skull unit 2A.

  The extracorporeal unit 3 includes an antenna 31, an antenna driving unit 32, a modulation unit 33, a demodulation unit 34, a power supply unit 35, a control unit 36, and a signal processing unit 37.

  As shown in FIG. 2, the electrode body 1, the light guide 4, and the upper skull units 2 </ b> A and 2 </ b> B are installed inside the subject 100 and can communicate with the upper skull units 2 </ b> A and 2 </ b> B outside the subject 100. In the state where the extracorporeal unit 3 is installed, the brain function measuring apparatus including these components collects brain function related information reflecting the brain activity of the subject 100 by the following operation.

  In the extracorporeal unit 3, the power supply unit 35 drives the antenna 31 via the antenna driving unit 32 so as to radiate electromagnetic waves having a predetermined frequency from the antenna 31. In the skull units 2A and 2B, the power supply unit 224 receives the electromagnetic wave via the antenna 220 to generate power, and supplies this to each part of the circuit. In other words, in this example, the cranial units 2A and 2B do not have a built-in power source such as a battery, and generate a necessary power based on electromagnetic waves received from the outside via the antenna 220. Have. Of course, it is good also as a structure which incorporates a battery in the skull unit 2B.

  In the extracorporeal unit 3, the control unit 36 generates various control signals for brain function measurement based on, for example, instructions given from the outside. This control signal is modulated by the modulation unit 33 into a predetermined format (such as a frequency band suitable for radio wave transmission through the antennas 31 and 220), and is transmitted from the antenna 31 via the antenna drive unit 32. The above-cranial unit 2 receives the above-mentioned signal via the antenna 220 and demodulates it by the demodulator 223 to extract the original control signal, and the controller 225 determines the signal processor 226 and the ID based on this control signal. The operation of the storage unit 227 and the like is controlled. Basically, the ID read from the ID storage unit 227 is modulated into a predetermined format by the modulation unit 222 and sent out from the antenna 220 via the antenna drive unit 221.

  As described above, when an electrical stimulus is applied to the brain through the electrode body 1 that contacts the brain surface of the subject 100, the stimulation current signal output from the control unit 225 passes through the contact unit 21 to the electrode body 1. The current signal is sent from the distal end portion 12 of the electrode body 1 to the brain. When optical stimulation is given to the brain through the light guide 4 that contacts the brain surface of the subject 100, the LED 228 emits light according to the stimulation signal output from the control unit 225, for example, near infrared light. Is transmitted to the light guide 4 through the optical coupling portion 23, and near-infrared light is irradiated from the distal end portion 42 of the light guide 4 to the brain.

  On the other hand, one electrode body 1 that contacts the brain surface of the subject 100 picks up a weak signal due to the cortical field potential near the contact site or the action potential of nerve tissue. This electric signal is input to the skull unit 2B via the contact portion 21. In addition, one light guide 4 in contact with the brain surface of the subject 100 is reflected by the brain surface, cerebral groove, or the like according to near infrared light irradiated from another light guide 4 as described above, for example. Collected light, scattered light, or light emitted by excitation. This light is guided through the light guide 4 and reaches the optical sensor 229 via the optical coupling unit 23, and is photoelectrically converted by the optical sensor 229 to generate an electrical signal corresponding to the received light intensity. All of these electrical signals are amplified by the signal processing unit 226, and multiplexing such as frequency multiplexing and time division multiplexing is performed as necessary. Then, the signal is modulated into a predetermined format by the modulation unit 222 and transmitted from the antenna 220 via the antenna driving unit 221.

  In the extracorporeal unit 3, the antenna 31 receives radio waves that are transmitted from the antenna 220 of the upper skull unit 2 and arrive through the scalp 101 of the subject 100 as described above. Then, the received signal is demodulated by the demodulator 34 and then processed by the signal processor 37, and collected by the ID unique to the upper skull unit 2 </ b> B, the electrical signal obtained by each electrode body 1, and each light guide 4. The electrical signal derived from the optical signal is separated and extracted. The electrical signals respectively obtained by the many electrode bodies 1 arranged two-dimensionally include important information regarding brain activity. In addition, for example, as described above, reflected light and scattered light respectively obtained by a large number of light guides 4 arranged two-dimensionally in response to near-infrared light irradiated on the brain surface Contains important information about blood flow. Therefore, according to the brain function measuring apparatus of this embodiment, the collection of electrical information such as brain waves over a two-dimensional predetermined range of the brain and the collection of optical information such as optical topography are performed in real time in parallel. be able to. Of course, only electrical measurement may be performed without performing optical measurement.

  As described above, in the brain function measuring apparatus according to the present embodiment, the upper skull units 2A and 2B that exchange signals wirelessly with an external unit outside the subject 100 are easily attached to and detached from the skull 102. The upper skull units 2A and 2B and the electrode body 1 and the light guide body 4 at least partially in contact with the brain are configured to exchange electrical signals and optical signals simply by contact. As described above, the above-mentioned skull units 2A and 2B have a complicated electric circuit section 22 built in, and often fail or the function becomes old and needs to be updated. In such a case, as long as the scalp 101 of the subject 100 is incised, the above-cranial units 2A and 2B can be easily replaced or removed. On the other hand, since the electrode body 1 and the light guide body 4 embedded in the skull 102 or the artificial skull can be used almost semi-permanently, there is basically no need for a surgical operation such as incising the skull 102. Stable measurement over a long period of time is possible by minimizing the burden on the patient and reducing the risk of infectious diseases.

  Here, the skull units 2A and 2B and the extracorporeal unit 3 are provided in a one-to-one relationship, but one extracorporeal unit 3 communicates with a plurality of the skull units 2A and 2B to control signals and It is good also as composition which exchanges measurement data. That is, at least one extracorporeal unit 3 is sufficient even when multipoint measurement is performed.

  Moreover, it is set as the structure which can mutually communicate between several cranium units 2A and 2B, and you may enable it to perform the measurement which several cranium units 2A and 2B cooperated. For example, in addition to performing simultaneous measurements on all the skull units 2A and 2B, it is also possible to measure a number of the skull units 2A and 2B arranged so as to cover the entire brain by shifting the time in a predetermined pattern. Is possible. As described above, by performing a measurement in which the plurality of overhead units 2A and 2B are networked, it is possible to perform a complicated and advanced measurement that cannot be achieved by a conventional device.

  Further, the above-described embodiment is merely an example of the present invention, and it is apparent that the present invention is encompassed by the claims of the present application even if appropriate modifications, corrections, or additions are made within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Electrode body 11 ... Shaft part 12 ... Tip part 13 ... Base part 14 ... Insulating coating 100 ... Subject 101 ... Scalp 102 ... Skull 103 ... Brain dura 104 ... Arachnoid 105 ... Cerebral cortex 110 ... Recess 2A, 2B ... Skull Upper unit 21 ... contact part 22 ... electric circuit part 220 ... antenna 221 ... antenna drive part 222 ... modulation part 223 ... demodulation part 224 ... power supply part 225 ... control part 226 ... signal processing part 227 ... ID storage part 228 ... LED
229 ... Optical sensor 23 ... Optical coupling unit 24 ... Holding member 25, 27 ... Screw 26 ... Flange 3 ... Extracorporeal unit 31 ... Antenna 32 ... Antenna drive unit 33 ... Modulation unit 34 ... Demodulation unit 35 ... Power supply unit 36 ... Control unit 37 ... Signal processing unit 4 ... Light guide 41 ... Shaft part 42 ... Tip part 43 ... Base

Claims (8)

A brain function measuring device for collecting information related to brain functions of subjects including various experimental animals and humans,
a) It is inserted into a through-hole drilled in a skull of a subject or an artificial skull attached to the subject instead of a part of the skull, and a distal end portion is exposed to the inside of the skull or the artificial skull. A plurality of electrodes in contact with a membrane covering the brain, while a base is exposed to the outside of the skull or artificial skull;
b) a contact part that is detachably fixed to the outside of the skull or artificial skull and that is exposed to the outside of the skull or artificial skull; and a contact part that contacts the base part of the plurality of electrodes; A signal relay unit that wirelessly transmits the electrical signal obtained or the electrical signal applied to the electrode via the contact part to the outside of the subject's scalp, or receives from the outside, a skull unit,
c) an extracorporeal unit that is provided outside the scalp of the subject, receives a signal transmitted wirelessly from the signal relay unit of the above-cranial unit, or transmits a signal wirelessly to the signal relay unit;
A brain function measuring device comprising: The brain function measuring device according to claim 1,
Similar to the plurality of electrodes, it is inserted into a through-hole drilled in the skull or artificial skull of the subject, and the tip is exposed to the inside of the skull or artificial skull to contact the brain or a membrane covering the brain On the other hand, a light guide formed by exposing a base portion to the outside of the skull or artificial skull,
The upper skull unit includes an optical coupling unit optically coupled to a base of the light guide exposed outside the skull or the artificial skull, and an optical signal to the brain through the optical coupling unit and the light guide. And a light receiving unit that receives an optical signal obtained through the light guide and the optical coupling unit and converts it into an electrical signal. The brain function measuring device according to claim 1 or 2,
The brain function measuring device, wherein the contact part and / or the optical coupling part of the above-cranial unit are two-dimensionally arranged on one surface of the casing of the unit. The brain function measuring device according to any one of claims 1 to 3,
The brain function measuring device, wherein the upper skull unit is fitted into a concave portion formed outside a skull of a subject or an artificial skull attached to the subject. A brain function measuring method for collecting information related to the brain function of subjects including various experimental animals and humans,
a) A plurality of through holes are drilled in the skull of the subject or an artificial skull to be attached to the subject instead of a part of the skull, and the tip of each through hole is exposed inside the skull or the artificial skull. And the electrode is inserted so that the base is exposed to the outside of the skull or artificial skull while contacting the brain or the membrane covering the brain,
b) Further, contact portions that respectively contact the base portions of the plurality of electrodes that are exposed to the outside of the skull or the artificial skull, and electrical signals obtained from the electrodes via the contact portions or via the contact portions A signal relay unit that wirelessly transmits an electrical signal to be applied to the electrode to the outside of the subject's scalp or receives from the outside, and the contact unit is a base of the plurality of electrodes, respectively. After detachably fixing to the outside of the skull or artificial skull so as to contact,
An electrical signal obtained by the electrode whose tip is in contact with the subject's brain or a membrane covering the brain is transmitted to the signal relay unit of the above-cranial unit via the contact part in contact with the base of the electrode. A brain function measuring method characterized in that the brain function related information is acquired by receiving a signal transmitted wirelessly in the signal relay unit by an extracorporeal unit provided outside the body of the subject. The brain function measuring method according to claim 5,
Similarly to the plurality of electrodes, the base portion is exposed to the inside of the skull or artificial skull and contacts the brain or a membrane covering the brain, in the through hole drilled in the skull or artificial skull of the subject. Inserted a light guide so that is exposed to the outside of the skull or artificial skull,
An optical coupling unit optically coupled to the base of the light guide exposed outside the skull or artificial skull, and a light emitting unit for providing an optical signal to the brain through the optical coupling unit and the light guide; A light receiving unit that receives an optical signal obtained through the light guide and the optical coupling unit and converts the received optical signal into an electrical signal, and provides stimulation of the optical signal to the brain, and / or The method for measuring brain function, characterized in that optical information is collected from the brain. The brain function measuring method according to claim 5 or 6,
A concave portion corresponding to the outer shape of the casing of the upper skull unit is formed outside the skull of the subject or the artificial skull attached to the subject, and the upper skull unit is fitted into the concave portion. A brain function measuring method characterized by the above. The brain function measuring method according to any one of claims 5 to 7,
A brain function characterized in that the range in which brain function-related information can be collected is expanded by fixing a plurality of the above-mentioned skull units on the outside of the skull of the subject or the artificial skull attached to the subject. Measurement method.

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