JP2013240485A - Brain wave measuring electrode and cap with brain wave measuring electrode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brain wave measuring electrode which secures conduction between the electrode and a scalp and does not make the hair get dirty by providing stretchability for absorbing the difference of the shape of the head when measuring brain waves and also having flexibility for easily getting into the hair and reducing pains at a part in contact with the scalp.SOLUTION: A brain measuring electrode 1 has both stretchability and flexibility since it includes: a metal plate 3; a cylindrical member 4 which is erected from the metal plate 3; a metal spring part 2a which is housed so as to be compressed in an axial direction in the cylindrical member 4, and is in contact with the metal plate 3 at a proximal end; and a metallic spherical distal end part 2c which is positioned outside the cylindrical member 4, can be brought into contact with a measurement object, and is connected so as to be swung and turned to a free end of the metal spring part 2a through a metal wire part 2b. Thus, when measuring brain waves, the conduction of the electrode and the scalp can be secured while absorbing the difference of the shape of the head without making the hair get dirty.

Description

  The present invention relates to an electroencephalogram measurement electrode and a cap with an electroencephalogram measurement electrode comprising the electroencephalogram measurement electrode.

  Research on the use of brain waves as a brain machine interface has attracted attention in recent years, and is expected to be widely used not only in medical diagnosis and research in the field of neuroscience but also in research and application in the engineering field.

  In order to measure an electroencephalogram, an electroencephalogram measurement electrode needs to contact the head. At present, a form generally used as a multi-channel electroencephalogram measurement method is that an electroencephalogram cap is attached with a large number of electroencephalogram electrodes, and measurement is carried out by wearing it. However, the problem with this form is that the shape of the head is different for each person, so the shape of the electroencephalogram cap does not necessarily fit the head, so there are parts where the electrodes do not contact the head. Is a point.

  Until now, contact has been made by putting a conductive gel in this non-contact portion. However, if the gel is used, the hair becomes dirty, so that usability is poor and wearing takes time. For example, since it takes about 1 to 2 minutes per electrode, it takes about 20 to 40 minutes for a general 20 channel.

  Therefore, currently, an electrode that does not use gel, ie, a dry electrode, has been developed, but the problem is how to make this dry electrode contact the head to ensure conduction between the dry electrode and the scalp. It has become. In the case of a conductive gel, since the gel enters between and behind the hair, conduction between the electrode and the scalp is ensured even if the hair exists between the electrode and the scalp. However, in the dry electrode type that does not use the gel, it is also important to devise a shape of an electrode that can enter between hairs and ensure conduction with the scalp.

  As described above, the conventional electroencephalogram measurement technology uses a gel to measure an electroencephalogram by bringing an electrode into contact with the scalp (for example, see Non-Patent Documents 1 and 3) and a dry electrode without using a gel. There exists a technique (for example, nonpatent literature 2) which measures an electroencephalogram using. Japanese Unexamined Patent Application Publication No. 2011-120866 discloses an electroencephalogram measurement electrode in which a protruding portion in contact with the head is formed of a conductive polymer composition or a metal material.

JP 2011-120866 A

Internet home page, g.tec medical engineering [Search February 17, 2012] “g.LADYbird” http://www.gtec.at/Products/Electrodes-and-Sensors/g.Electrodes-Features Internet homepage, g.tec medical engineering [Search February 17, 2012] “g.SAHARAelectrode (16 mm)” http://www.gtec.at/Products/Electrodes-and-Sensors/g.Electrodes- Specs-Features Internet homepage, g.tec medical engineering [Search February 17, 2012] Page 63 http://www.gtec.at/content/download/4932/40206/version/2/#

  As for the electrode in the technique for measuring brain waves using the gels disclosed in Non-Patent Documents 1 and 3, the electroencephalogram can be measured from all the electrodes as a result of ensuring the conduction between the electrodes and the scalp by the gel. There is an advantage. However, there is a problem that the hair becomes dirty due to the gel and the hair needs to be washed, and it takes time to wear all the electrodes because the gel is injected into each of the electrodes, and the subject is burdened. On the other hand, the electrode disclosed in Non-Patent Document 2 that uses a dry electrode to measure brain waves without using a gel is not very dirty and has a short wearing time compared to the case of using a gel. Has the advantage of being excellent. However, since the shape of the head is different for each person, there is a problem that the electrode does not contact the scalp, and the brain wave cannot be measured at that part. As a result, a situation occurs in which an appropriate inspection result cannot be obtained and the inspection must be repeated. Moreover, since the contact state is likely to be unstable due to the hair sandwiched between the electrode and the scalp, it is necessary that the electrode can enter between the hairs. The electrode disclosed in Non-Patent Document 2 is a sword mountain type electrode having a protrusion so that it can enter between hairs.

  The electroencephalogram measurement electrode disclosed in Patent Document 1 is flexible when the projection is a conductive gel of a polymer composition, and has an elasticity when the projection is a metal material. Is an invention of an electrode. When the conductive gel of the polymer composition is used for the protruding part of the electrode, it has flexibility and can easily enter between the hairs, ensuring conduction, and the pain of the part hitting the scalp is reduced. There is an effect. However, the conductive gel of the polymer composition is unlikely to remain on the hair unlike conventional gels, but when the conductive gel protrusions come into contact with the scalp or hair, it becomes dirty and feels creamy and sticky. Remains. In addition, in an electrode in which the protruding portion is made of a metal material, the protruding portion for conduction coming out from the electrode is not expandable / contractable, and can be expanded / contracted by attaching a spring around the protruding portion. However, the projecting portion itself cannot be flexible. Therefore, it is conceivable that the electrodes are difficult to enter between the hairs, and the contact state with the scalp is unstable, so there is a possibility that an appropriate test result cannot be obtained. Furthermore, due to the lack of flexibility, it is conceivable that the pain in the portion that comes into contact with the scalp occurs in the subject in combination with the fact that no processing is performed on the tip of the metal projection. That is, Patent Document 1 does not disclose an electroencephalogram measurement electrode in which the hair is not soiled, is stretchable, and is flexible.

  The present invention has been made in view of the above circumstances, has elasticity to absorb the difference in the shape of the head, and more easily enters between hairs or reduces pain in the part in contact with the scalp. Therefore, an object of the present invention is to provide an electroencephalogram measurement electrode that has flexibility so as to ensure conduction between the scalp and the electrode with a metal that does not contaminate the hair.

  In order to achieve the above object, an electroencephalogram measurement electrode according to the present invention is accommodated in a metal plate, a cylindrical member standing from the metal plate, and axially compressible in the cylindrical member, and a proximal end is the metal A metal spring part in contact with the plate, and a metal spring which is located outside the cylindrical member and can be contacted with a measurement object, and is connected to the free end of the metal spring part via a metal wire part so as to be able to swing and turn. And a spherical tip.

  Further, in the electroencephalogram measurement electrode of the present invention, a plurality of cylindrical members are erected from one metal plate, each cylindrical member contains a metal spring portion, and the metal spring portion has a spherical shape via a metal wire portion. It is characterized by a continuous tip.

  In the electroencephalogram measurement electrode of the present invention, the length of the metal spring portion in the longitudinal direction is longer than the length of the cylindrical member in the longitudinal direction.

  Moreover, this invention is a cap with an electrode for electroencephalogram measurement provided with the electrode for electroencephalogram measurement described above.

  The present invention has the following effects.

  The electrode for electroencephalogram measurement of the present invention includes a metal plate, a cylindrical member erected from the metal plate, a metal spring portion which is accommodated in the cylindrical member so as to be compressible in the axial direction, and a proximal end is in contact with the metal plate, Since it is located outside the cylindrical member and is capable of contacting a measurement object, the metal spring portion includes a metal spherical tip that is connected to the free end of the metal spring portion so as to be swingable and pivotable. When measuring the electroencephalogram, it is possible to ensure the conduction between the electrode and the scalp while absorbing the difference in the shape of the head, that is, the unevenness. Further, since the electroencephalogram measurement electrode is made of metal, the hair is not soiled. Furthermore, since the tip is spherical, the pain in the part in contact with the scalp is reduced.

  In the present invention, the electroencephalogram measurement electrode has a plurality of cylindrical members erected from a single metal plate, each cylindrical member containing a metal spring portion, and the metal spring portion having a spherical shape via a metal wire portion. Since the tips are connected, it is possible to measure the electroencephalogram with high accuracy.

  In the present invention, since the electroencephalogram measurement electrode has a longer length in the longitudinal direction of the metal spring portion than a length in the longitudinal direction of the cylindrical member, the amount of movement between the metal wire portion connected to the metal spring portion and the tip portion is small. By increasing the size, flexibility can be further exhibited.

  Moreover, the electroencephalogram cap provided with the electroencephalogram measurement electrode of the present invention can be provided with the electroencephalogram measurement electrode having both stretchability and flexibility. Therefore, when the electroencephalogram is measured, it is possible to secure the electrical connection between the electrode and the scalp while absorbing the difference in the shape of the head simply by wearing the cap with the electroencephalogram measurement electrode. In addition, since it is made of metal, it is possible to provide an electroencephalogram measurement cap that is excellent in usability such that the hair is not soiled.

FIG. 1 is a front view showing a form of an electroencephalogram measurement electrode of the present invention. FIG. 2 is a bottom view showing the form of the electroencephalogram measurement electrode. FIG. 3 is an explanatory view showing a use state of the electroencephalogram measurement electrode. FIG. 4 is a front view showing another embodiment of the electroencephalogram measurement electrode of the present invention. FIG. 5 is an explanatory view showing a use state of a cap with an electroencephalogram measurement electrode equipped with the same electroencephalogram measurement electrode.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a front view of an electroencephalogram measurement electrode 1 according to an embodiment of the present invention. As shown in FIG. 1, the electroencephalogram measurement electrode 1 of the present invention includes an electrode portion 2 made of a conductive metal, a metal plate 3, and a cylindrical member 4. Here, silver (Ag), platinum (Pt), gold (Au), or the like can be used as the conductive metal. The electrode portion 2 is formed of a metal spring, and includes a metal spring portion 2a having an outer diameter smaller than the inner diameter of the cylindrical member 4, a metal wire portion 2b, and a spherical tip portion 2c. Here, for example, a metal spring such as a SUS spring can be used for the metal spring portion 2a. Next, the metal wire portion 2b has a diameter of about 0.5 mm, and silver (Ag) is used here. The metal wire portion 2b is coated with, for example, cashew paint in order to provide electrical insulation. Furthermore, the spherical tip portion 2c has a spherical portion with a diameter of about 1 mm, and silver (Ag) is used here. On the other hand, the diameter of the metal spring part 2a and the metal wire part 2b is 1 mm or less. Here, one end of the metal spring portion 2a is in contact with the metal plate 3, and the other end is provided with a spherical tip portion 2c continuous through the metal wire portion 2b. The metal spring portion 2a in the electrode portion 2 is accommodated in a cylindrical member 4 made of a synthetic resin such as an acrylic pipe or a conductor such as a shield that contacts the metal plate 3. Here, the metal plate 3 is in perpendicular contact with the cylindrical member 4. Note that the upper surface of the metal plate 3 is a conductive portion with the preamplifier.

  Here, since the metal spring portion 2a itself in contact with the metal plate 3 is a metal spring, the electroencephalogram measurement electrode 1 has elasticity. When the electroencephalogram measurement electrode 1 is not used, the metal spring portion 2a remains long, but when worn, the metal spring portion 2a is retracted in the cylindrical member 4 in contact with the metal plate 3 and is then moved to the head. Because of the contact, the specificity of the shape of the individual's head can be absorbed. Therefore, there is a part where the electrode does not contact the scalp in the prior art due to the uniqueness of the shape of the head, and even if the electroencephalogram cannot be measured at that part, the electroencephalogram can be measured. Furthermore, since the metal spring portion 2a is a metal spring, the electroencephalogram measurement electrode 1 also has flexibility. In addition, the diameter of the metal spring portion 2a and the metal wire portion 2b of the electrode portion 2 is as thin as 1 mm or less, and the tip portion 2c enters between the hairs while swinging and turning, and comes into contact with the scalp. Therefore, the conduction between the electrode and the scalp is ensured without using conductive gel and without contaminating the hair. Furthermore, an appropriate test result can be obtained without the contact state becoming unstable due to the hair sandwiched between the electrode and the scalp. In addition, the movement amount when the electrode part 2 enters between hairs can be adjusted with the length of the metal wire part 2b which is not covered with the cylindrical member 4. FIG.

  Moreover, since the tip portion 2c of the electrode portion 2 is spherical, the pain in the portion in contact with the scalp is reduced although it is a metal that does not stain the hair. The cylindrical member 4 also has an effect of preventing the metal spring portion 2a from being distorted.

  FIG. 2 is a bottom view of the electroencephalogram measurement electrode 1 according to the embodiment of the present invention. In the electroencephalogram measurement electrode 1 of the present invention, the electrode portion 2 and the cylindrical member 4 can be installed on a plurality of metal plates 3. In FIG. 2, the metal wire portion 2 b and the tip portion 2 c of the three electrode portions 2, the three cylindrical members 4, and the metal plate 3 are shown. Various diameters of the metal plate 3 are conceivable depending on the size of the electrode, and may be 10 mm, for example. Here, the three electrode portions 2 are arranged so that the centers of the inscribed circles of the three electrode portions 2 coincide with the centers of the metal plates 3. It is desirable that the three electrode portions 2 be arranged as close as possible.

  In the embodiment of the present invention, the number of electrode portions 2 is three, but may be more than three. Arranging as many electrode portions 2 as possible on the metal plate 3 in a narrow space by arranging the electrode portions 2 so that the centers of the inscribed circles of the plurality of electrode portions 2 coincide with the centers of the metal plates 3. Can do. In such a case, the electrode portion 2 can also be arranged inside the inscribed circle.

  FIG. 3 is a diagram for explaining an example of use of the electroencephalogram measurement electrode 1 according to the embodiment of the present invention. In the electroencephalogram measurement electrode 1 of the present invention, as shown in FIG. 3, when measuring an electroencephalogram, the elastic metal spring portion 2a in contact with the metal plate 3 contracts in the cylindrical member 4, and the spherical tip portion 2c. Can contact the head 5 and measure the electroencephalogram. Furthermore, since the electroencephalogram measurement electrode 1 also has flexibility due to the metal spring portion 2a, the electroencephalogram measurement electrode 1 enters between the hairs 7 and the back of the hair. Is secured.

  FIG. 4 is a front view showing 1a which is an example of another embodiment of the electroencephalogram measurement electrode 1 according to the embodiment of the present invention. As shown in FIG. 4, the electroencephalogram measurement electrode 1 a according to the present invention is longer in the longitudinal direction of the metal spring portion 2 a than in the longitudinal direction of the cylindrical member 4. The other parts have the same structure as the electroencephalogram measurement electrode 1. Therefore, during electroencephalogram measurement, the metal spring portion 2a that is in contact with the metal plate 3 is contracted in the cylindrical member 4, but in this embodiment, the metal spring portion 2a is located outside the cylindrical member 4. . Therefore, the portion located outside the cylindrical member 4 in the metal spring portion 2 a has a large elasticity, so that the electroencephalogram measurement electrode 1 a can exhibit greater flexibility than the electroencephalogram measurement electrode 1. Therefore, during electroencephalogram measurement, the amount of movement of the metal wire portion 2b and the tip portion 2c connected to the metal spring portion 2a of the electroencephalogram measurement electrode 1a in the hair becomes larger than that of the electroencephalogram measurement electrode 1. Therefore, the electroencephalogram measurement electrode 1a is easier to enter between the hairs than the electroencephalogram measurement electrode 1, and can further ensure conduction. In this embodiment, the flexibility can be adjusted by adjusting the stiffness of the metal spring portion 2a of the electroencephalogram measurement electrode 1a.

  FIG. 5 is a view for explaining an example of use in the cap 6 with an electroencephalogram measurement electrode including the electroencephalogram measurement electrode 1 according to the embodiment of the present invention. The electroencephalogram measurement electrode 1 of the present invention has a stretchability in contact with the metal plate 3 when the electroencephalogram cap 6 to which a plurality of the electroencephalogram measurement electrodes 1 are attached is attached when measuring an electroencephalogram as shown in FIG. Since the metal spring portion 2 a having the electrode member 2 contracts in the cylindrical member 4 semi-automatically, the length of the electrode portion 2 changes, and the spherical tip portion 2 c comes into contact with the head portion 5. Therefore, the specificity of the shape of the individual's head is absorbed, and the electroencephalogram can be measured. In addition, since the electroencephalogram measurement electrode 1 also has flexibility by the metal spring portion 2a, the electroencephalogram measurement electrode 1 enters between or behind the hairs, so even if the hair exists between the electrodes and the scalp, no conductive gel is used. Conductivity between the electrode and the scalp is ensured without polluting the hair. Even when a custom-made EEG cap modeled from an individual's head is created, the fit state of the EEG cap changes depending on the amount of hair when actually worn. Therefore, in such a case, it is considered that the electrode does not contact the head conventionally. However, even in such a case, since the electroencephalogram measurement electrode 1 of the present invention has stretchability and flexibility, electrical connection between the electrode and the scalp is ensured and the electroencephalogram can be appropriately measured. In the present embodiment, the electroencephalogram cap 6 is used on the assumption that the electroencephalogram is measured at about 20 locations across the entire head from the frontal head to the back of the head. However, in the case of simply measuring an electroencephalogram, two or three electroencephalogram measurement electrodes 1 are installed in a headband shape to measure an electroencephalogram at the frontal region, or a headset shape or a headband shape. For example, the electroencephalogram measurement electrode 1 can be installed on a human body, and an electroencephalogram can be measured only at a necessary site such as the back of the head or the top of the head. In addition, the electroencephalogram can be measured at a high density by using the electrodes 1 for measuring the electroencephalogram 1 and using many electrodes such as 128 or 256.

  A case where an electroencephalogram is measured using the electroencephalogram measurement electrode cap 6 of FIG. 5 will be described below. When the electroencephalogram measurement electrodes 1 are arranged at 20 locations on the head 5, electroencephalogram measurement can be performed at all locations within a few seconds per electrode, and several tens of types using conventional gels. It was possible to install in a minute. In addition, in the conventional dry electrode type of the prior art, even if there is a part that did not contact the head and the electroencephalogram measurement could not be performed, the electroencephalogram measurement can be performed by using the electroencephalogram measurement electrode 1. It was. That is, since the electroencephalogram measurement electrode 1 has elasticity and flexibility, it is possible to measure electroencephalograms from all electrodes even when the shape of the head has specificity, and it is made of metal. Since it is not necessary to use a conductive gel, it has been confirmed that the invention combines the advantages of the prior art with excellent usability that the hair is not soiled and the wearing time is short.

DESCRIPTION OF SYMBOLS 1,1a Electroencephalogram measurement electrode 2 Electrode part 2a Metal spring part 2b Metal wire part 2c Tip part 3 Metal plate 4 Cylindrical member 5 Head 6 Cap with electroencephalogram measurement electrode 7 Hair

Claims (4)

A metal plate,
A cylindrical member erected from the metal plate;
A metal spring portion accommodated in the cylindrical member so as to be compressible in the axial direction, a base end of which contacts the metal plate;
A metal spherical tip that is located outside the cylindrical member and is capable of contacting a measurement object and is connected to the free end of the metal spring portion so as to be swingable and pivotable via a metal wire portion. Electrode for measuring EEG features.   A plurality of cylindrical members are erected from one metal plate, each cylindrical member contains a metal spring portion, and a spherical tip portion is connected to the metal spring portion via a metal wire portion. The electrode for electroencephalogram measurement according to 1.   3. The electroencephalogram measurement electrode according to claim 1, wherein the length of the metal spring portion in the longitudinal direction is longer than the length of the cylindrical member in the longitudinal direction.   A cap with an electroencephalogram measurement electrode comprising the electroencephalogram measurement electrode according to any one of claims 1 to 3.

Images