JPH063537Y2 - EEG measurement probe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a probe for measuring an electroencephalogram.

[Prior art and its problems]

To measure the electroencephalogram, for example, 21
A large number of individual EEG electrodes must be attached. As the electroencephalogram electrode, there are a needle electrode used by puncturing the scalp and a dish-shaped electrode adhered to the scalp with a paste. At present, a silver-monochloride silver-plated electrode is often used because of its safety and electrical characteristics. To measure EEG with a silver silver chloride plate electrode,
Since it is necessary to fix the electrolytic solution on the scalp by some method, bentonite or the like is added to the electrolytic solution to form a paste. That is, the silver paste for conductivity is applied to the surface of the electrode made of a silver plate, and the paste is applied one by one to the skin of the head at a predetermined site with a tape coated with an adhesive. Therefore, it takes a few hours to prepare before starting the measurement, and at the time of attaching and detaching the silver plate, the subject is not a little distressed. Then, after removing the silver plate, it was necessary to wash the head to remove the silver paste. Moreover, the silver plate of the electrode has a size of about 1 cm ² , and even if it is pasted with a paste, impurities are likely to intervene between the electrodes, and thus the measurement is likely to be inaccurate, but the skin of the head is further affected. If the cells were keratinized, the impedance and potential difference between the skin of the head and the electrodes became large, making accurate measurement difficult. Moreover, since the paste is dried and the resistance increases with the lapse of time, it is difficult to measure for a long time.

Therefore, it is conceivable to contact the head with a probe composed of a half-cell composed of an electrode and an electrode arranged in a chip capable of exuding the electrolytic solution to measure an electroencephalogram. In the measuring method using such a probe, the electrolytic solution that has exuded from the chip wets the skin of the head and conducts electricity. However, if the electrolytic solution is washed away during the measurement for about 30 minutes and becomes insufficient, electrical conduction becomes poor and accurate measurement cannot be performed. Therefore, a mechanism for constantly supplying the electrolytic solution to the chip is required, which causes a problem that the structure becomes complicated.

[Purpose of device]

Therefore, the present invention can easily and surely make contact with the skin of a predetermined part of the head, does not cause any pain to the subject, and does not require a mechanism for supplying an electrolyte solution to the chip and has a simple structure. It is an object of the present invention to provide a probe for measuring an electroencephalogram that can be accurately measured without increasing resistance even when measured for a long time.

[Constitution of the device and its action]

The electroencephalogram measurement probe of the present invention is characterized in that the electrolytic solution is gelled with agarose and protrudes from the tip of the chip, and the electrode is placed in electrical connection with the agarose gel.

That is, a half-battery is composed of an electrolytic solution gelled with agarose and an electrode placed in conduction with this agarose gel, and when the agarose gel is brought into contact with the skin of the head, the gelled electrolytic solution Wet the skin of the head and conduct electricity. And, if this probe is attached to a predetermined position of the helmet, for example, when this helmet is worn on the head,
Since the agarose gel of a predetermined number of probes simultaneously contacts the skin of the head, silver paste, adhesive tape, etc. are not required, the mounting operation is very simple, and the subject is not hurt. In addition, since the electrolytic solution is agarose gel, it has a shape-retaining ability, does not flow away during measurement, and the amount of evaporation is small, but the evaporation does not reduce the gel volume itself and the resistance does not increase. . Since the agarose gel has a low impurity ratio and contains almost no charged components such as SO ₃ groups, it does not affect ionic conduction or electron conduction. Therefore, the electrolytic solution supply mechanism is not required, the structure is simple, and accurate measurement can be performed for a long time.

〔Example〕

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

In FIG. 1, the tip 1 is made of a soft plastic tube such as polyethylene or polypropylene and has an opening at its tip. Then, the chip 1 is filled with the electrolytic solution 2 gelled with agarose, and its tip projects from the chip 1. Electrolyte solution 2 is KCl, RbCl, CsCl, NaC
An aqueous solution of chloride such as l, LiCl, CaCl ₂ and MgCl ₂ is used, which is gelled by agarose. Agarose, which is known as the main component of agar, is a polysaccharide represented by the formula [C ₁₂ H ₁₄ O ₅ (OH) ₄ ] n, most of which is D-galactose and 3.6-. Anhydro-L
-Consisting of galactose only. Agarose, which is such a component, has a low impurity ratio and contains almost no charged components such as SO ₃ groups. In addition, the gelled product of such agarose has a characteristic that the gel volume shrinks in accordance with the evaporation of the electrolytic solution. Then, the silver-silver monochloride electrode 3 is arranged in contact with the gel electrolyte 2, and the electrode 3 and the electrolyte 2 form a half-cell. As the electrode 3, a calomel electrode, a platinum electrode, a gold electrode, a hydrogen electrode, an amalgam electrode, a carbon electrode, or the like can be used in addition to silver silver chloride. The conductor wire 4 is connected to the electrode 3 and extends to the outside.

A predetermined number of such probes are attached to a predetermined position of the helmet 5 formed of, for example, acrylic resin.
Then, when measuring the electroencephalogram, the subject may wear the helmet 5 on the head as shown in FIG. As a result, regardless of the shape of the head of the subject, a predetermined number of gelled electrolyte solutions 2 simultaneously contact the head and wet the head at a predetermined position of the head, and the electrolyte 2 causes the electrode 3 to move. The brain wave can be measured accurately because it is conducted with.

As described above, a predetermined number of probes can be accurately mounted at a predetermined position at the same time only by wearing the helmet 5 to which the probe is attached on the head. Therefore, the operation is very simple, and the subject is detached when the probe is attached or detached. Has the advantage of not causing pain. Further, since the electrolytic solution 2 is gelled with agarose, it has a shape-retaining ability and is not washed away during measurement,
The amount of evaporation is also small. Therefore, it is not necessary to constantly supply a low-viscosity electrolytic solution to the chip, and the structure is extremely simple. In addition, since agarose has a low impurity ratio and contains almost no charged components such as SO ₃ groups, it does not affect ionic conduction or electron conduction, and even if the electrolytic solution 2 evaporates, the gel volume corresponding to it does not increase. Also contracts, so the resistance value does not increase. Therefore, accurate measurement can be performed for a long time.

[Effect of device]

As described above, the brain wave measuring probe of the present invention is
The electrolyte is gelled with agarose and protrudes from the tip of the chip, and the electrode is placed in electrical connection with this agarose gel, so if this probe is attached to a helmet, for example, it can be easily applied to the skin at a predetermined site on the head, In addition, it is possible to provide a brain wave measuring probe that can reliably contact the tip, has a simple structure, and can accurately measure for a long time.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is an explanatory view of a usage state. 1 ... Chip, 2 ... Electrolyte, 3 ... Electrode 4 ... Conductive wire, 5 ... Helmet

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location 8119-4C A61B 5/04 300 M

Claims (1)

[Scope of utility model registration request] 1. A probe for measuring an electroencephalogram characterized in that an electrolytic solution is gelled with agarose and protrudes from the tip of a chip, and an electrode is placed in a conductive state with the agarose gel.