JP2012095939A - Biomagnetism measurement device and method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost and space in obtaining biological information with a magnetic sensor.SOLUTION: A magnetic sensor (32) employs TMR elements for measuring weak magnetism at ordinary temperatures without cooling, in particular, using liquefied gas. A plurality of the magnetic sensors (32) are disposed on a biological body 2, while a cover member 4 is disposed so as to cover the magnetic sensors (32) to shield the magnetic sensors and portions to be measured from an external magnetic field. Thus, there is no need to cool the sensors by using the liquefied gas unlike a SQUID (Superconducting QUantum Interference Device) which is a conventional device for measuring weak currents in the biological body, and there is no need to magnetically shield the whole room, thereby drastically reducing cost and space and dramatically facilitating maintenance. Furthermore, no insulating member is needed which has been necessary in the SQUID, and the sensors and the biological body are brought close to each other to prevent displacement as seen in the SQUID, and crossing of magnetic fields is minimized, thereby also improving position resolution.

Description

  The present invention relates to an apparatus and method for biomagnetic measurement represented by magnetoencephalography.

  Conventionally, in biomagnetic measurements represented by the above-mentioned magnetoencephalography, a SQUID (Superconducting Quantum Interference Device), which is a highly sensitive magnetic sensor that detects a weak magnetic field, has been used. The rough measurement mechanism is that when superconductors with different phases are joined via a barrier layer (Josephson junction), a tunnel current flows between the superconductors, and the tunnel current is a magnetic flux penetrating the junction surface. It uses the Fraunhofer-type quantum interference effect, which is weakened when is an integral multiple of the flux quantum and strengthened at other times. Such a property is called the Josephson effect, and a device in which one or more Josephson junctions are connected by a superconducting loop is called the SQUID.

  Most of the SQUID elements currently in practical use are made of niobium (Nb), and in order to work as a SQUID element, it is necessary to make this niobium into a superconducting state as described above. Since the superconducting transition temperature is 9.2K, cooling with liquid helium is required. Therefore, in actual measurement, liquid helium is circulated, and a large number of these elements are arranged and fixed in the concave surface at the bottom of the pot cooled to a low temperature of about 10K, and the subject's head is placed in the concave surface for measurement. I am serving.

  Patent documents 1-5 etc. are proposed as such a SQUID sensor and a magnetoencephalography measuring device using the same. In particular, as shown in Patent Document 1, SQUID has a problem that the cost and space are very large because of cooling with liquid helium. In addition, when the Josephson element fails, the maintenance burden is heavy, such as the need to remove the liquid helium once.

  On the other hand, the structure of the sensor portion is not a structure that flexibly follows the subject's head, but is simply a structure in which the head is put into a hard concave surface portion, so that the scalp and the concave surface cannot be in close contact with each other, and a gap is generated. Moreover, even if the head is in close contact with the concave surface, the heat insulation layer has a thickness of 3 to 4 cm for heat insulation between the cooled sensor and the head, and the SQUID sensor is separated from the site to be inspected accordingly. Therefore, even though the SQUID sensor alone is high in magnetic sensitivity, the SQUID sensor is arranged away from the site to be inspected, so the magnetic field entering the sensor becomes weak, and adjacent magnetic fields intersect to input to one SQUID. Therefore, there is a problem that the position resolution in measurement is greatly reduced. In addition, if the posture changes for each measurement or if there is body movement during measurement, the positional relationship between the brain and the SQUID sensor changes, causing a large measurement error. There is also.

  On the other hand, Non-Patent Document 1 shows an example of an electrocardiogram measurement using an MI (magnetic impedance) element that can perform weak magnetic measurement at room temperature. When such a method is used, it is not necessary to cool the sensor. Therefore, there is no restriction such as SQUID, and these elements can be brought into close contact with the human body directly. The close contact can avoid misalignment, improve the position resolution, and eliminate the need for a heat insulating layer.This makes it possible to perform close-up measurements and improve the position resolution before the adjacent magnetic fields intersect. Measurement in a high state and a strong magnetic field is also possible. Thus, it is possible to achieve an improvement in resolution as a measuring device.

JP 2000-193364 A JP 2004-65605 A JP 2007-17248 A JP-A-2-40578 Japanese Patent Laid-Open No. 3-1839

“A Measurement of Magnetocardiogram (MCG) by Planar Type Sensor using CoNbZr FILM” Y.Ohtomo, S. Yabukami, K. Kato, T. Ozwa and I, Arai (Journal of Magnetics Society of Japan Vol.33, No.3, 2009)

  By the way, since the biomagnetic field is very weak, a dedicated magnetic shield is required. Conventional measuring devices such as SQUID are very large, and are installed in a dedicated magnetic shield room in order to shield all of them from external magnetism. In general, permalloy used for a magnetic shield takes time and labor for processing and installation, and is very expensive. Since this expensive permalloy covers the entire room, its installation cost was very expensive. Moreover, since it was necessary to install in a magnetic shield room, carrying was practically impossible. Although the above-mentioned non-patent document 1 does not particularly describe the magnetic shield, it is presumed that this is also performed in a dedicated magnetic shield room.

  An object of the present invention is to provide a biomagnetic measurement apparatus and method that can realize a magnetic shield in a simple and inexpensive manner.

  The biomagnetic measuring device of the present invention includes a plurality of magnetic sensors attached to a living body, a measuring device main body that collects information on a weak current generated in the living body from measurement results of the magnetic sensors, and the living body And a covering member that covers and shields the magnetic sensor attached to the external magnetic field.

  The biomagnetic measurement method of the present invention includes a step of attaching a plurality of magnetic sensors for detecting a magnetic field due to the weak current to the living body, and collecting the information on the weak current generated in the living body. A step of covering the magnetic sensor with a covering member that shields from an external magnetic field, and a step of collecting information on a weak current generated in the living body from a measurement result of each magnetic sensor. .

  According to the above configuration, when acquiring biological information by attaching a magnetic sensor to a living body, the magnetic sensor is not particularly cooled by liquefied gas, and can perform weak magnetic measurement in a normal temperature range. A (tunnel magnetoresistive) element, a GMR (giant magnetoresistive) element, an MI (magnetic impedance) element, or an optically pumped magnetic measuring element is used, and a plurality of the magnetic sensors are provided on the living body. And the information regarding the weak electric current which arose in the said biological body is collected with the measuring device main body from the measurement result of each said magnetic sensor. On the other hand, a covering member is provided on the living body so as to cover the magnetic sensor attached to the living body, thereby shielding the magnetic sensor and the measured part from an external magnetic field.

  Therefore, cooling with a liquefied gas such as SQUID, which is a conventional measuring device for weak current in a living body, becomes unnecessary, and the cost and space can be greatly reduced, and the maintenance becomes much easier. In addition, the heat insulation member necessary for the SQUID is not required, the distance between the sensor and the living body is brought closer, occurrence of misalignment as seen in the SQUID is suppressed, and the crossing of magnetic fields is also minimized. The resolution can also be improved. Furthermore, since the entire room such as the SQUID is not magnetically shielded but only the periphery of the portion to be measured is shielded, the cost of the magnetic shield can be significantly reduced and the degree of freedom in measurement is improved. be able to.

  As described above, the biomagnetic measuring device and method of the present invention are not subjected to cooling with liquefied gas and are not cooled by a liquefied gas. An element capable of weak magnetic measurement is used, and a plurality of the magnetic sensors are provided on the living body, and a covering member is provided so as to cover the magnetic sensor, thereby shielding the magnetic sensor and the measured part from an external magnetic field.

  Therefore, cooling with a liquefied gas such as SQUID, which is a conventional measurement apparatus for weak current in a living body, is not required, and the cost and space can be greatly reduced, and maintenance is greatly facilitated. In addition, the heat insulation member necessary for the SQUID is not required, the distance between the sensor and the living body is brought closer, occurrence of misalignment as seen in the SQUID is suppressed, and the crossing of magnetic fields is also minimized. The resolution can also be improved. Furthermore, since the entire room such as the SQUID is not magnetically shielded but only around the portion to be measured, the cost of the magnetic shield can be greatly reduced, and electromagnetic waves are generated near the living body. Other measurement devices and the like can be arranged, and other measurement devices that generate electromagnetic waves in the vicinity of the living body can be arranged, and the degree of freedom in measurement can be improved.

It is sectional drawing which shows typically the use condition of the biomagnetic measuring apparatus which concerns on the 1st Embodiment of this invention. It is a front view which shows typically the use condition of the sensor unit in the biomagnetic measuring device which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the electrical structure of the said biomagnetic measuring device. It is a block diagram which shows the electric constitution of the interface in FIG. It is a block diagram which shows the electric constitution of a sensor platform board. It is sectional drawing which shows typically the use condition of the biomagnetic measuring device which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the said biomagnetic measuring device. It is a front view which shows typically the use condition of the biomagnetic measuring device which concerns on the 3rd Embodiment of this invention. It is a front view of the test subject who uses the biomagnetic measuring device shown in FIG. It is sectional drawing of the biomagnetism measuring device shown in FIG.

(Embodiment 1)
FIG. 1 is a cross-sectional view schematically showing a use state of the biomagnetic measurement device 1 according to the first embodiment of the present invention. The biomagnetism measuring apparatus 1 according to the present embodiment measures the magnetism emitted from the head 21 of the subject 2 and obtains a magnetoencephalogram. Specifically, the biomagnetic measuring apparatus 1 measures a magnetic field generated from an electric current that flows when a brain neuron is excited, for example, where an epileptic seizure occurs, how far the brain operation is performed (the cell is dead) It is used to determine if it can be excised.

  In this biomagnetic measuring device 1, the head 21 of the subject 2 is first covered with the sensor unit 3 as shown in FIG. The sensor unit 3 is made of a non-magnetic material, and is formed by mounting a large number of sensor platform boards 32 side by side on a support 31 formed in a so-called balaclava type. As a result, a large number of sensor platform boards 32 are distributed at predetermined intervals on either the front or back surface of the support 31. Then, as shown in FIG. 2, the sensor unit 3 is placed on the human head 21 so as to press the inner surface of the support 31 along the surface of the head 21. The sensor surface of the sensor platform board 32 is along the surface at regular intervals (through contact or through the thickness of the support 31). The sensor platform board 32 is an assembly of magnetic sensors that do not require cooling with a liquefied gas and can perform weak magnetic measurement in a normal temperature range.

  The opening 33 of the eye 22 portion of the subject 2 in the support 31 takes into account the mental influence of the subject 2 and the like, and may not be provided depending on the circumstances such as the measurement site. In that case, it becomes possible to measure the magnetoencephalogram emitted from the face portion as well as the frontal region, the occipital region and the temporal region.

  It should be noted that in the biomagnetic measuring device 1 of the present embodiment, the sensor unit 3 is mounted on the head 21 of the subject 2 as described above, and then a covering member that performs magnetic shielding as shown in FIG. 4 is mounted and the measurement described later is executed. A magnetic shield chamber may be formed so as to surround the subject 2 in combination with the covering member 4. However, the magnetic shield room in that case is not a large-scale one used for the above-described SQUID, and may be a simple one.

  The covering member 4 covers at least one of the cheek, the nose, the mouth, the eyes, the jaw, and the neck in addition to the forehead, the occipital region, and the temporal region. In the example of FIG. 1, the covering member 4 has a shape of a so-called full-face helmet (a protective cap worn to protect the head from an impact or the like) covering all of them. The eyes and mouth correspond to the openings 33 of the support 31 described above.

  This is because it is necessary to prevent the entry of external magnetism into the head 21 when measuring brain magnetism. In that case, the magnetic entry path in question is not only from the surface side of the head 21 to be measured, This is because it can be a face portion corresponding to the back side of the human body when viewed from the measurement site, or can be an approach path from the jaw or throat direction. Therefore, by providing (extending) the covering member 4 that performs magnetic shielding in these directions as necessary, disturbances in magnetic measurement can be blocked and measurement accuracy can be improved. In addition, when the measured part is the head 21 as described above, the covering member 4 has a so-called helmet shape, so that the subject 2 only needs to cover the covering member 4 to obtain a necessary magnetic shield. The covering member 4 can be easily mounted.

  As the covering member 4, a commonly used permalloy shield is suitable. In that case, a thin layer of the permalloy is molded from a casting and annealed under a hydrogen atmosphere, and a plurality of layers from which distortion has been removed are laminated to form the covering member 4. For this reason, the covering member 4 is configured by assembling parts molded in a state of being half-cracked into the left and right or separated into the upper and lower sides into the helmet shape or the like by bonding or another support.

  As the magnetic sensor used for the sensor platform board 32, as described above, an element that does not require cooling with a liquefied gas and can perform weak magnetic measurement in a normal temperature range is used. For example, a TMR (tunnel magnetoresistance) element is used. , GMR (giant magnetoresistive) element, MI (magnetic impedance) element, or optically pumped magnetometer. As an application example of the MI (magnetic impedance) element to the living body magnetic measurement, the above-mentioned Non-Patent Document 1 can be cited, and as an application example of the optical pumping magnetic measurement element to the living body magnetic measurement, Anselm Deninger, Jurgen Stuhler, Wilhelm G. Kaenders, 'Biomagnetic Measurements Benefit from Laser Know-How, Atom magnetometers enable precise magnetic field measurements of the human heart and brain', [online], TOPTICA Photonics AG, [searched October 27, 2010] Internet <URL: http://www.toptica.com/uploads/media/toptica_AP_1011_laser_magneto_cardiography_2008_19.pdf>. In the present invention, any element described above may be used as long as the magnetic sensor can be adhered and fixed to a living body and necessary sensitivity can be obtained. An example will be described.

  FIG. 3 is a block diagram showing an electrical configuration of the biomagnetic measuring device 1 configured as described above. The biomagnetism measuring device 1 includes the sensor unit 3, a calculation device 5, and an interface 6. The arithmetic device 5 is composed of a personal computer or the like, and is connected to the sensor unit 3 via the interface 6. The sensor unit 3 and the interface 6 are connected by a cable 7. The sensor unit 3 can be freely moved within the reach of the cable 7, and the direction can be freely changed. The cable 7 includes a power line 71 and a signal line 72.

  FIG. 4 is a block diagram showing an electrical configuration of the interface 6. The interface 6 includes a PCI bus controller 61, a command conversion buffer controller 62, an SRAM 63, and a serial interface driver 64. The PCI bus controller 61 performs communication between the arithmetic device 5 and the command conversion buffer controller 62. The command conversion / buffer controller 62 transmits a command from the arithmetic unit 5 to each sensor unit 3, develops the measurement result transmitted from each sensor unit 3 as a serial signal, and writes it in the SRAM 63. At the same time, in response to a read request from the arithmetic device 5, the stored contents of the SRAM 63 are read and transmitted to the arithmetic device 5. The serial interface driver 64 performs communication between the command conversion / buffer controller 62 and each sensor platform board 32.

  FIG. 5 is a block diagram showing an electrical configuration of each sensor platform board 32. The sensor platform board 32 is electrically connected and mechanically fixed with TMR array modules 321, 321,... Including a plurality of TMR elements of several mm square arranged in an array. The sensor platform board 32 also includes a controller 322, a RAM 323, and amplification / conversion circuits 324, 324,. The amplification / conversion circuit 324 is provided for each TMR array module 321 and is connected to the TMR array module 321 on a one-to-one basis. The amplification / conversion circuit 324 includes an amplifier 324 a that amplifies the output signal from the TMR array module 321, and an A / D converter 324 b that converts the output of the amplifier 324 a into a digital signal and inputs the digital signal to the controller 322. The RAM 323 is a storage device that stores information input to the controller 322 and information calculated by the controller 322.

  The controller 322 receives a command from the arithmetic unit 5 and starts measurement, operates the TMR array module 321, sequentially takes the output signal through the amplification / conversion circuit 324, and stores it in the RAM 323. Thereafter, the controller 322 alternatively outputs the output signal of the TMR array module 321 to a predetermined timing at an appropriate timing (in response to polling from the arithmetic unit 5 or at a time predetermined for each controller 322). Is transmitted to the arithmetic unit 5 through the signal line 72 by serial communication in the format of.

  The arithmetic device 5 which is a measuring device main body collects information on the weak current generated in the living body, for example, information such as a position and a size flowing from the generation position, from the output signal of each TMR array module 321. In addition, although the deposition position on the living body (the head 21 of the subject 2) of each TMR array module 321 needs to be recognized by the arithmetic device 5 for each TMR array module 32, If each TMR array module 32 is deposited at a predetermined deposition position, or if each TMR array module 32 is deposited on a living body, the deposition position is measured and input to the arithmetic unit 5 Good.

  It is preferable to use a three-dimensional measuring device for measuring the position of the TMR array module 321 on the living body (head 21). Specifically, the alignment marker is first attached to the living body (head 21), and the location is measured and specified by an optical three-dimensional measuring device, CT, MRI, or the like. In this case, when the covering member 4 described later is worn, the position of the TMR array module 321 can be specified by wearing it together with the alignment marker. As the alignment position, it is more preferable to use a position of an ear or the like that does not move when overlapping with MRI or other measurement results.

  On the other hand, when the three-dimensional measuring apparatus is not used, the position measurement is performed by simultaneously measuring the position of the TMR array module 321 and the position of the living body (head 21) by CT scan having a high fluoroscopic effect. It can be carried out. In that case, since the information of the TMR array module 321 or the sensor platform board 32 can be obtained as CT scan information, accurate measurement can be performed by continuously performing such sensor and living body position measurement and the following biomagnetic measurement. Information can be linked as three-dimensional information.

  Subsequently, in the biomagnetism measurement, first, power is supplied to the entire biomagnetism measurement apparatus 1, and a current is also applied to each TMR array module 321. As a result, under the influence of the magnetic flux generated from the head 21 of the subject 2, the magnetization direction of the free magnetic layer changes in each TMR element in the TMR array module 321 and the fixed magnetic layer According to the angle difference between the magnetization direction and the magnetization direction of the free magnetic layer, the resistance of the nonmagnetic insulating layer changes due to the tunnel effect. As a result, the voltage between the voltage detection electrodes of the TMR element changes, and this becomes an output signal corresponding to the change in resistance of the TMR element.

  Next, a measurement execution command is input to the arithmetic device 5 by the operator. Then, the arithmetic device 5 sends a measurement execution command to the n sensor platform boards 32. In each sensor platform board 32, the controller 322 receives a measurement execution command. The controller 322 receives a digitized output signal from each TMR array module 321 via the amplification / conversion circuit 324, and links it to information specifying the address information of each TMR array module 321. Is sent to the arithmetic unit 5 as biomagnetic measurement information.

  The arithmetic device 5 analyzes biomagnetic measurement information from each controller 322, calculates a magnetoencephalogram comprising a combination of the position on the head 21 of the subject 2 and the strength and direction of the magnetic field, and converts it into image information. Display on the display device 51. In addition, the arithmetic device 5 generates a composite image in which the positions of the biomagnetic measurement information image and the MRI image of the head 21 of the subject 2, the three-dimensional scan image of the head outline, and the like are displayed. A display is output to the device 51.

  As the measurement execution command, one measurement execution command may be provided, but a measurement start command and a measurement end command may be provided. In the period between the measurement start command and the measurement end command, it is effective to execute measurement at a constant time rate and display a magnetoencephalogram that changes in real time on the display device 51. In addition, biomagnetic measurement information, magnetoencephalogram information, and image information generated for display are recorded so as to be readable by the arithmetic device 5 and can be displayed and reproduced on the display device 51.

  Prior to such measurement, as described above, the covering member 4 is provided on the living body (the head 21 of the subject 2) to shield the sensor unit 3 and the measured part from an external magnetic field. That is, as described above, the subject 2 to whom the TMR array module 321 is fixed by measuring the relative position with the measurement target in advance by CT, MRI or the like further wears the covering member 4 that shields from the external magnetic field.

  Therefore, cooling with a liquefied gas such as SQUID, which is a conventional measuring device for weak current in a living body, becomes unnecessary, and the cost and space can be greatly reduced, and the maintenance becomes much easier. In addition, the heat insulation member necessary for the SQUID is not required, the distance between the sensor unit 3 and the living body (head 21) is reduced, the occurrence of displacement as seen with the SQUID is suppressed, and the crossing of magnetic fields is minimized. The position resolution can also be improved since it is limited to the limit. Furthermore, since the entire room such as the SQUID is not magnetically shielded but only the periphery of the portion to be measured is shielded, the cost of the magnetic shield can be significantly reduced, and the vicinity of the living body (head 21). Another measuring device (calculation device 5) that generates an electromagnetic wave can also be arranged on the device, and the degree of freedom in measurement can be improved.

  Further, when the measurement target is the head 21, the covering member 4 has a so-called helmet shape, so that the subject 2 can perform the necessary magnetic shielding only by covering the covering member 21. It is possible to easily attach the covering member.

(Embodiment 2)
FIG. 6 is a cross-sectional view schematically showing a use state of the biomagnetic measurement device 1a according to the second embodiment of the present invention, and FIG. 7 is a cross-sectional view of the biomagnetic measurement device 1a. It should be noted that in the biomagnetic measurement apparatus 1a, the sensor platform board 32, which is a magnetic sensor, is lined on the helmet-shaped covering member 4a. That is, in the two members of the outer shell-shaped cap body constituting the so-called helmet and the cushioning interior body filled in the inside, the above-described covering member 4 is formed only by the cap body. On the other hand, the covering member 4 a of the present embodiment is configured to include a cap body 41 and an interior body 42. The configuration of the remaining calculation device 5 and the like is the same as that of the biomagnetic measurement device 1 described above, and a description thereof is omitted.

  The interior body 42 is made of a sufficiently flexible material (compared to a vehicle or the like). As long as the material does not cause a significant change in the magnetic permeability, it may be a material particularly used in ordinary clothing. Specifically, cotton, polypropylene, polyethylene, etc. may be used. it can.

  When the subject 21 wears the covering member 4a, the entire head 21 is covered with a flexible cushion, and the sensor platform board 32 is brought into close contact with the head 21 by the sinking of the interior body 42. In order to ensure respiration, the front part of the mouth 23 and the nose 24 in the interior body 42 has a concave shape.

  Since the purpose of the covering member 4 is also an electromagnetic shield, the size of the head 21 of the user 2 is so large that it is formed in a large size and does not shift in the balustrade-type support 31. Depending on the situation, a cushioning material may be appropriately interposed. Since the inner body 42 is made of a nonmagnetic material, the sensor platform board 32 may be lined on the cap body 41 due to the routing of the cable 7 or the like. However, the position resolution can be improved by lining the interior body 42 due to the influence of the crossing of the magnetic fields.

  With this configuration, the sensor platform board 32 is preliminarily integrated (incorporated) into the covering member 4a, so that the subject 2 only wears the covering member 4a and wears the sensor platform board 32. Can be easily installed. In addition, the sensor platform board 32 is positioned in the covering member 4a, and the sensor platform board 32 can be easily and closely fixed to a predetermined mounting position by using the covering member 4a that matches the shape of the head 21 of the subject 2. can do.

  In integrating the sensor platform board 32 with the covering member 4a in this way, as shown by the reference numeral 4h in FIG. 7, a mounting opening for the sensor platform board 32 is formed in the covering member 4a. After the covering member 4a is mounted, the magnetic measurement may be performed by attaching the sensor platform board 32 from the attachment opening 4h.

  In this case, the mounting depth of the sensor platform board 32 can be easily adjusted, and the sensor platform board 32 can be easily adhered to the living body (head 21). Further, the sensor position can be easily measured by substituting the measurement position of the sensor platform board 32 with the position of the mounting opening 4h in the covering member 4a. That is, the sensor platform board 32 requires means for outputting a magnetically measured signal to the outside, and this means is generally achieved by the cable 7 such as an electric wire or an optical fiber. Therefore, if only the covering member 4a that performs magnetic shielding is present, these cables 7 are not present, so there is no blind spot when performing optical 3D measurement, and the measurement is facilitated. Even if the measurement is performed by the technical means, there is no restriction by the cable 7, so that the subject 21 can easily move into the measurement device.

  Preferably, as shown in FIG. 7, a stimulator 81 that provides somatic sensory stimulation that does not generate a magnetic field is provided inside the covering member 4 a. It is effective to give somatosensory stimuli such as mechanically pushing the skin and observe the response in order to observe in detail the response to the brain activity and other nerve stimuli, and the physiological response. Because. The stimulator 81 includes a nonmagnetic bearing that can be inserted from the outside of the covering member 4a, a rod, a cable, a tube, a needle, a cylinder, an optical fiber, a link mechanism, and the like (in FIG. 7, the face 25 is pressed). (Indicated by cylinder).

  Therefore, by providing the stimulating device 81 on the covering member 4a that performs magnetic shielding, or by providing an attachment mechanism thereof, somatic sensory stimulation can be applied, and desired observation becomes possible.

  Further, preferably, as shown in FIG. 7, an image display device 82 for providing a visual stimulus that does not generate a magnetic field is provided inside the covering member 4a. This is because in order to observe the brain activity and the like in detail, it is effective to see the reaction to the stimulus by the visual information. As the image display device 82, only the projection is performed, and the portion for generating the image information in which the magnetic field is generated is placed outside the covering member 4a, and the image is taken out from the portion using an optical fiber or the like, and is placed in the covering member 4a. The image is projected on the arranged image display device 82 and presented to the subject 2. In this way, visual stimulation can be applied, and desired observation is possible. Further, by using in combination with the somatosensory stimulation by the stimulator 81 described above, it is possible to observe a biological reaction to a complex stimulus.

(Embodiment 3)
FIG. 8 is a front view schematically showing the usage state of the biomagnetic measurement device 1b according to the third embodiment of the present invention. The biomagnetism measuring apparatus 1b according to the present embodiment measures magnetism emitted from the chest 26 and abdomen 27 of the subject 2 shown in FIG. When the measurement target is the chest 26, the myoelectric potential (contraction pulse) of the heart 28 is measured and, for example, the measurement result is overlapped with CT, MRI or the like, thereby confirming whether there is an abnormality in the operation of the heart 28. it can. In addition, when the part to be measured is the abdomen 27, the magnetic field generated from the fetal heart of the pregnant woman at rest can be measured, the movement of the fetal heart can be understood, and can be used for prenatal examinations, etc. Damage can be confirmed.

  10 is a cross-sectional view of FIG. In this biomagnetic measuring device 1b, it should be noted that the covering member 4b is formed in a cylindrical shape suitable for the chest part 26 and the trunk part 27. The rest of the configuration of the computing device 5 and the like is the same as that of the biomagnetic measuring devices 1 and 1a described above, and a description thereof is omitted. The covering member 4b is also lined with the sensor platform board 32, which is a magnetic sensor. And this coating | coated member 4b is comprised from two members of the outer side cylindrical body 41b which performs a magnetic shield, and the buffering interior body 42b with which it is filled, for example as shown in FIG. It is possible to divide the long axis line of the elliptical cross section perpendicular to the axis, that is, before and after the subject 2.

  The two divided parts 4b1 and 4b2 may be connected at one end side by a hinge or the like and fastened at the other end side by a hook or the like, or may be fastened by a hook or the like at both ends. The material of the interior body 42b is the same as that of the interior body 42 described above. When performing measurement by raising the upper body of the subject 2 such as sitting in a chair or standing, the covering member 4b is provided with a shoulder strap-like fixture 43 so as not to slide down. It is also preferable to improve the close contact with the living body.

  In order to express the present invention, the present invention has been properly and fully described through the embodiments with reference to the drawings. However, those skilled in the art can easily change and / or improve the above-described embodiments. It should be recognized that this is possible. Accordingly, unless a modification or improvement implemented by a person skilled in the art is at a level that significantly departs from the scope of the claims recited in the claims, the modification or the improvement is not entitled to the claims. It is interpreted as encompassing the scope.

1, 1a, 1b Biomagnetic measurement device 2 Subject 21 Head 22 Eye 23 Mouth 24 Nose 25 Face 26 Chest 27 Abdomen 28 Heart 3 Sensor unit 31 Support body 32 Sensor platform board 321 TMR array module 322 Controller 323 RAM
324 Amplification / Conversion Circuit 324a Amplifier 324b A / D Converter 33 Opening 4, 4a, 4b Covering Member 4b1, 4b2 Part 4h Mounting Opening 41 Cap Body 41b Tubular Body 42, 42b Interior Body 5 Arithmetic Unit 51 Display Device 6 Interface 61 PCI Bus Controller 62 Command Conversion Buffer Controller 63 SRAM
64 Serial interface driver 7 Cable 71 Power line 72 Signal line 81 Stimulator 82 Image display device

Claims (9)

A plurality of magnetic sensors attached to a living body;
From a measurement result of each magnetic sensor, a measuring device main body that collects information on a weak current generated in the living body,
A biomagnetic measurement apparatus comprising: a covering member that covers the magnetic sensor attached to the living body and shields it from an external magnetic field.   The biomagnetism measuring apparatus according to claim 1, wherein the covering member covers at least one of a cheek, a nose, a mouth, an eye, a jaw, and a neck in addition to the forehead, the occipital region, and the temporal region.   The biomagnetism measuring apparatus according to claim 2, wherein the covering member has a helmet shape.   The biomagnetism measuring apparatus according to claim 1, wherein the covering member is a cylindrical body that covers the trunk.   The biomagnetic measuring device according to claim 3 or 4, wherein the magnetic sensor is lined on the covering member.   The biomagnetic measuring apparatus according to claim 3 or 4, wherein an attachment opening for the magnetic sensor is formed in the covering member, and magnetic measurement is possible by attaching the magnetic sensor from the attachment opening.   The biomagnetism measuring apparatus according to any one of claims 1 to 6, wherein a stimulator that provides somatic sensory stimulation that does not generate a magnetic field is provided inside the covering member.   The biomagnetism measuring apparatus according to claim 1, wherein an image display device that provides a visual stimulus that does not generate a magnetic field is provided inside the covering member. In collecting information on the weak current generated in the living body,
Attaching a plurality of magnetic sensors to the living body to detect a magnetic field due to the weak current;
Covering the magnetic sensor attached to the living body with a covering member that shields from an external magnetic field;
Collecting information on the weak current generated in the living body from the measurement result of each magnetic sensor.

Images