WO2005048837A1 - Electrode structure for measuring electrical responses from the human body - Google Patents

Electrode structure for measuring electrical responses from the human body Download PDF

Info

Publication number
WO2005048837A1
WO2005048837A1 PCT/FI2004/000687 FI2004000687W WO2005048837A1 WO 2005048837 A1 WO2005048837 A1 WO 2005048837A1 FI 2004000687 W FI2004000687 W FI 2004000687W WO 2005048837 A1 WO2005048837 A1 WO 2005048837A1
Authority
WO
WIPO (PCT)
Prior art keywords
electrode
measuring
electrode structure
silver
hole
Prior art date
Application number
PCT/FI2004/000687
Other languages
French (fr)
Inventor
Henri Hannula
Matti Aho
Marko Ollikainen
Original Assignee
Nexstim Oy
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nexstim Oy filed Critical Nexstim Oy
Priority to JP2006540480A priority Critical patent/JP4510027B2/en
Priority to CN2004800338277A priority patent/CN1882281B/en
Priority to US10/579,832 priority patent/US7440789B2/en
Priority to EP04798296.2A priority patent/EP1684630B1/en
Publication of WO2005048837A1 publication Critical patent/WO2005048837A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/25—Bioelectric electrodes therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/25—Bioelectric electrodes therefor
    • A61B5/279—Bioelectric electrodes therefor specially adapted for particular uses
    • A61B5/291—Bioelectric electrodes therefor specially adapted for particular uses for electroencephalography [EEG]
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/25—Bioelectric electrodes therefor
    • A61B5/279—Bioelectric electrodes therefor specially adapted for particular uses
    • A61B5/296—Bioelectric electrodes therefor specially adapted for particular uses for electromyography [EMG]
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2562/00—Details of sensors; Constructional details of sensor housings or probes; Accessories for sensors
    • A61B2562/02—Details of sensors specially adapted for in-vivo measurements
    • A61B2562/0209—Special features of electrodes classified in A61B5/24, A61B5/25, A61B5/283, A61B5/291, A61B5/296, A61B5/053
    • A61B2562/0215—Silver or silver chloride containing

Definitions

  • Electrode Structure for Measuring Electrical responses from the Human Body
  • the present invention relates to an electrode structure according to the preamble of Claim 1.
  • the invention also relates to a measuring cap and a manufacturing method.
  • measurements made from the surface of the head are made using silver electrodes for measuring electrical responses, for example, in TMS (transcranial magnetic stimulation) tests, in which an electromagnetic pulse is directed to the brain and the response it creates is measured using electroencephalograph (EEG) measuring equipment.
  • EEG electroencephalograph
  • electrically polarizing interfaces arise between the different materials in the silver electrodes according to the prior art and lead to interference signals that diminish the accuracy of the measurement.
  • the silver electrodes are chloridized, in an attempt to eliminate this phenomenon. Despite this measure, satisfactory results are not always achieved. As chloridization only affects the surface of the electrode, it is easily removed by wear or, for example, by unintentionally scratching the electrode. Chloridization must be performed regularly between measurements, leading to additional work and preventing continuous use of the electrodes.
  • the electrode structures become detached easily during washing and are difficult to reattach.
  • the invention is intended to eliminate the defects of the state of the art disclosed above and for this purpose create an entirely new type of electrode structure.
  • the invention is based on the fact that the smaller the electrode, the smaller the electrical currents induced by a magnetic stimulation pulse, which fact is exploited in the invention by making the electrode thin in the thickness direction of the electrode structure, and by equipping the electrode structure with holes and locating the electrode at the edge of the hole, so that its longitudinal axis is essentially parallel to the plane of the measurement subject.
  • One preferred embodiment of the invention is, on the other hand, based on the realization that, if an electrode made from silver/silver-chloride is used, the electrode surface will also remain essentially unaltered, even if the electrode wears or is scratched, because the electrode consists throughout of the same material.
  • a third preferred embodiment of the invention is based on using small electrodes made from silver-chloride pellets, which can be installed in a measurement hood using a snap- fit attachment.
  • the electrode structure according to the invention is characterized by what is stated in the characterizing portion of Claim 1.
  • the measuring cap according to the invention is, in turn, characterized by what is stated in the characterizing portion of Claim 12.
  • the solution according to the invention permits electrical responses to be measured during, or a short time after the magnetic pulses produced by the magnetic stimulators, typically after 1 - 5 ms, even after a powerful magnetic pulse, particularly if the solution according to the invention is used in conjunction with magnetic stimulation simultaneously with suitable EEG equipment.
  • the electrode structure according to the invention forms a stable electrical contact between the person being measured and the electrode.
  • the attachment construction of the electrode is compact in size, thus permitting a TMS coil to be placed close to the surface of the head.
  • the coil's effective distance is about 30 mm and the effective electrical field induced diminishes rapidly as the distance increases.
  • the solution according to the invention permits the coil to be placed closer to the point it is wished to affect.
  • the value of a 5 - 30 % stronger electrical field is calculated from a distance difference of 2 - 3 mm, i.e. if the electrode's attachment were to be 2 - 3 mm thicker, the electrical field induced by TMS in the tissue would be correspondingly weakened.
  • the electrode structure 10 is entirely non-magnetic, i.e. the magnetization of all the structural materials is very small.
  • MEG magnetictoencephalography
  • the electrode structure (10) is constructed in such a way that a special tool is needed to detach it, while, in addition, the construction protects the brittle silver-chloride electrode (1) from impacts, scratching, and wear.
  • the electrode structure according to the invention does not require chloridization, and thus interfaces that hamper measurements are not created in the electrode structure. When the electrode wears, its electrical properties remain unchanged.
  • the measurement point on the skin of the test person can be cleaned after the attachment of the electrode, as there is a sufficiently large hole (6) in the electrode structure.
  • the small size and compact shape of the electrode prevents the magnetic stimulation coil from inducing strong electromotor forces in the electrode and thus reduces the creation of eddy currents caused by the electrical fields.
  • Figure 1 shows a bottom view of one electrode structure according to the invention.
  • Figure 2 shows a side view of the electrode structure according to Figure 1.
  • Figure 3 shows a cross-sectional side view along the line A-A of the sensor according to the invention.
  • Figure 4 shows a cross-sectional view along the line B-B of the electrode structure according to Figure 2.
  • Figure 5 shows an exploded perspective view of the electrode structure according to the invention.
  • Figure 6 shows a perspective view of the electrode structure according to the invention.
  • Figure 7 shows a perspective view of electrode structures according to the invention, located on a measuring cap.
  • the electrode structure according to the invention is examined from beneath, in other words, from the direction of the measurement subject.
  • the electrode structure 10 includes a body piece 2, from which a measuring lead 4 protrudes. Electrical contact from the measurement subject, typically a person's scalp, to the electrode material, is formed through the hole 6, with the aid of an electrically conductive past. According to the figure, the electrode structure 10 is essentially discshaped.
  • Figure 2 shows the locking piece 3 connected to the body piece, by means of which the measuring cap described later is locked between the body piece and the locking piece.
  • the locking piece 3 is located on the outer surface of the electrode structure, if the inner surface is defined as the measuring surface, for example, the scalp.
  • FIG 3 shows the construction of the measuring electrode 10 in greater detail.
  • the measuring opening 6 extends through the entire structure and the piece 3 locks onto the body piece 2 with the aid of locking lugs.
  • the electrode 1 made from silver/silver- chloride is located at the very edge of the opening 6, thus forming a contact with the contact paste (not shown) in the hole 6.
  • the electrode 1 is typically connected to the measuring lead 4 with the aid of a silver connector lead 5.
  • the connection of the electrode 1, which the connector lead 5 also permanently forms part of, to the measuring lead 4 demands special measures, for example, there must be no silver/silver-chloride spatters in the silver wire 5 and the soldering of the measuring lead 4 and the silver wire must not touch the electrode 1, as the hot solder will melt the Ag-AgCl mass, ?? which? is made by sintering, and form an interface with it, which may, in turn, cause interference in the measuring situation.
  • the electrode pellet 1 typically has a cylindrical shape, so that its longitudinal axis is parallel to the measuring surface. This alignment gives the electrode structure 10 a flat dimension, which is as small as possible, between the measuring surface 13 and the outer surface.
  • the dimension of the electrode 1 in the thickness direction of the electrode structure 10 is, according to the invention, small, preferably less than 5 mm, and most preferably less than 2 mm.
  • the term thickness of the electrode 1 refers to its dimension in the direction of the thickness of the electrode structure 10, in other words, for example, the left-to-right dimension in Figure 3.
  • the term measuring situation refers, for example, to a measurement made after a stimulation pulse.
  • Non-magnetic plastic which is dry-machined, is used as the raw material for the plastic components 2 and 3. This is done, because the machining liquid used in the machining centre may contain magnetic materials, which would hamper measurement.
  • the peak value of the density of the magnetic flux caused by the oscillation of the electrode 10 should be less than 80 femtotesla in a shielded enclosure, in which there is a dc field of 30 nanotesla.
  • the cross-section of the body piece 2 is essentially circular.
  • a curved opening arrangement, in which the locking piece 3 is locked, is made in the circular piece 2.
  • the electrode 1 extends to the hole 6 in the electrode structure.
  • the brittle electrode 1 is tightly inside the body structure 2.
  • Figures 5 and 6 show a perspective view of additional details of the invention.
  • the upper surface of the locking piece 3 is essentially annular in shape and forms a uniform flat surface on the side opposite to the measuring surface.
  • the electrode structures are placed at regular intervals in the cap 7 and the cap is placed around the skull.
  • the measuring leads of the measuring cap are wound into a tight, preferably spiral bundle, in order to reduce interference.
  • the earth and reference electrode leads of the measuring cap are wound tightly together, to reduce interference. Interference can be further reduced by running the measuring leads from the electrodes towards the front of cap 11.
  • the electrode structure can deviate from a disc-like shape and flat angular and elliptical shapes too are quite possible.
  • the use of curved surfaces between the body 2 and locking 3 pieces achieves a more even locking effect.
  • the electrode 1 of the electrode structure 10 is so small in size that a cross-section through any plane at all of the electrode 1 will have a surface area of less than 15 mm 2 , more preferably of less than 4 mm 2 .
  • the small size is important, in order to reduce the electrical field caused by induction and the eddy currents arising in the electrode 1.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Medical Informatics (AREA)
  • Biophysics (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Physics & Mathematics (AREA)
  • Molecular Biology (AREA)
  • Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)

Abstract

The invention relates to an electrode structure (10) for attachment to a more extensive measuring structure (11), in order to measure electrical responses from the human body. The electrode structure (10) includes a conductive electrode (1). According to the invention, the electrode (1) is shaped to be thin in the thickness direction of the electrode structure (10), and the electrode structure (10) is equipped with a hole (6) and the electrode (1) is located at the edge of the hole (6), in such a way that its longitudinal axis is essentially parallel to the plane of the measurement subject.

Description

Electrode Structure for Measuring Electrical responses from the Human Body
The present invention relates to an electrode structure according to the preamble of Claim 1.
The invention also relates to a measuring cap and a manufacturing method.
According to the prior art, measurements made from the surface of the head in particular are made using silver electrodes for measuring electrical responses, for example, in TMS (transcranial magnetic stimulation) tests, in which an electromagnetic pulse is directed to the brain and the response it creates is measured using electroencephalograph (EEG) measuring equipment. In practice, electrically polarizing interfaces arise between the different materials in the silver electrodes according to the prior art and lead to interference signals that diminish the accuracy of the measurement.
The silver electrodes are chloridized, in an attempt to eliminate this phenomenon. Despite this measure, satisfactory results are not always achieved. As chloridization only affects the surface of the electrode, it is easily removed by wear or, for example, by unintentionally scratching the electrode. Chloridization must be performed regularly between measurements, leading to additional work and preventing continuous use of the electrodes.
In measurement caps according to the prior art, the electrode structures become detached easily during washing and are difficult to reattach.
The invention is intended to eliminate the defects of the state of the art disclosed above and for this purpose create an entirely new type of electrode structure.
The invention is based on the fact that the smaller the electrode, the smaller the electrical currents induced by a magnetic stimulation pulse, which fact is exploited in the invention by making the electrode thin in the thickness direction of the electrode structure, and by equipping the electrode structure with holes and locating the electrode at the edge of the hole, so that its longitudinal axis is essentially parallel to the plane of the measurement subject.
One preferred embodiment of the invention is, on the other hand, based on the realization that, if an electrode made from silver/silver-chloride is used, the electrode surface will also remain essentially unaltered, even if the electrode wears or is scratched, because the electrode consists throughout of the same material.
A third preferred embodiment of the invention is based on using small electrodes made from silver-chloride pellets, which can be installed in a measurement hood using a snap- fit attachment.
More specifically, the electrode structure according to the invention is characterized by what is stated in the characterizing portion of Claim 1.
The measuring cap according to the invention is, in turn, characterized by what is stated in the characterizing portion of Claim 12.
The method according to the invention is, in turn, characterized by what is stated in the characterizing portion of Claim 16.
Considerable advantages are gained with the aid of the invention.
The solution according to the invention permits electrical responses to be measured during, or a short time after the magnetic pulses produced by the magnetic stimulators, typically after 1 - 5 ms, even after a powerful magnetic pulse, particularly if the solution according to the invention is used in conjunction with magnetic stimulation simultaneously with suitable EEG equipment.
The electrode structure according to the invention forms a stable electrical contact between the person being measured and the electrode. The attachment construction of the electrode is compact in size, thus permitting a TMS coil to be placed close to the surface of the head. The coil's effective distance is about 30 mm and the effective electrical field induced diminishes rapidly as the distance increases. The solution according to the invention permits the coil to be placed closer to the point it is wished to affect. With the aid of the invention, it is possible to create in the brain a TMS-induced electrical field that is typically 5 - 30 % stronger than when using thicker electrode attachment constructions. The value of a 5 - 30 % stronger electrical field is calculated from a distance difference of 2 - 3 mm, i.e. if the electrode's attachment were to be 2 - 3 mm thicker, the electrical field induced by TMS in the tissue would be correspondingly weakened.
According to one preferred alternative of the invention, the electrode structure 10 is entirely non-magnetic, i.e. the magnetization of all the structural materials is very small.
For example, this is a great advantage and even an essential requirement in measurements made in connection with an MEG (magnetoencephalography) device. MEG compatibility is, in turn, a great advantage in laboratories and in applications, in which TMS and EEG, as well as MEG measurements are used. A non-magnetic structure is also very important if EEG measurements are made during MRI imaging
(Magnetic Resonance Imaging), for example, in connection with FMRI (Functional Magnetic Resonance Imaging) tests. The electrode structure (10) is constructed in such a way that a special tool is needed to detach it, while, in addition, the construction protects the brittle silver-chloride electrode (1) from impacts, scratching, and wear.
The electrode structure according to the invention does not require chloridization, and thus interfaces that hamper measurements are not created in the electrode structure. When the electrode wears, its electrical properties remain unchanged.
In addition, the measurement point on the skin of the test person can be cleaned after the attachment of the electrode, as there is a sufficiently large hole (6) in the electrode structure.
The small size and compact shape of the electrode prevents the magnetic stimulation coil from inducing strong electromotor forces in the electrode and thus reduces the creation of eddy currents caused by the electrical fields.
In the following, the invention is examined with the aid of an example of an embodiment according to the accompanying drawings.
Figure 1 shows a bottom view of one electrode structure according to the invention. Figure 2 shows a side view of the electrode structure according to Figure 1. Figure 3 shows a cross-sectional side view along the line A-A of the sensor according to the invention.
Figure 4 shows a cross-sectional view along the line B-B of the electrode structure according to Figure 2.
Figure 5 shows an exploded perspective view of the electrode structure according to the invention.
Figure 6 shows a perspective view of the electrode structure according to the invention. Figure 7 shows a perspective view of electrode structures according to the invention, located on a measuring cap.
According to Figure 1, the electrode structure according to the invention is examined from beneath, in other words, from the direction of the measurement subject. The electrode structure 10 includes a body piece 2, from which a measuring lead 4 protrudes. Electrical contact from the measurement subject, typically a person's scalp, to the electrode material, is formed through the hole 6, with the aid of an electrically conductive past. According to the figure, the electrode structure 10 is essentially discshaped.
Figure 2 shows the locking piece 3 connected to the body piece, by means of which the measuring cap described later is locked between the body piece and the locking piece. The locking piece 3 is located on the outer surface of the electrode structure, if the inner surface is defined as the measuring surface, for example, the scalp.
Figure 3 shows the construction of the measuring electrode 10 in greater detail. The measuring opening 6 extends through the entire structure and the piece 3 locks onto the body piece 2 with the aid of locking lugs. The electrode 1 made from silver/silver- chloride is located at the very edge of the opening 6, thus forming a contact with the contact paste (not shown) in the hole 6. The electrode 1 is typically connected to the measuring lead 4 with the aid of a silver connector lead 5. The connection of the electrode 1, which the connector lead 5 also permanently forms part of, to the measuring lead 4 demands special measures, for example, there must be no silver/silver-chloride spatters in the silver wire 5 and the soldering of the measuring lead 4 and the silver wire must not touch the electrode 1, as the hot solder will melt the Ag-AgCl mass, ?? which? is made by sintering, and form an interface with it, which may, in turn, cause interference in the measuring situation. The electrode pellet 1 typically has a cylindrical shape, so that its longitudinal axis is parallel to the measuring surface. This alignment gives the electrode structure 10 a flat dimension, which is as small as possible, between the measuring surface 13 and the outer surface. The dimension of the electrode 1 in the thickness direction of the electrode structure 10 is, according to the invention, small, preferably less than 5 mm, and most preferably less than 2 mm. The term thickness of the electrode 1 refers to its dimension in the direction of the thickness of the electrode structure 10, in other words, for example, the left-to-right dimension in Figure 3.
In this case, the term measuring situation refers, for example, to a measurement made after a stimulation pulse. Non-magnetic plastic, which is dry-machined, is used as the raw material for the plastic components 2 and 3. This is done, because the machining liquid used in the machining centre may contain magnetic materials, which would hamper measurement.
A particularly advantageous result is achieved, if a magnetization value less than that given below is achieved.
If the electrode construction is oscillated with an amplitude of about 5 cm at a distance of 3 cm from a sensor measuring the density of the magnetic flux, the peak value of the density of the magnetic flux caused by the oscillation of the electrode 10 should be less than 80 femtotesla in a shielded enclosure, in which there is a dc field of 30 nanotesla.
According to Figure 4, the cross-section of the body piece 2 is essentially circular. A curved opening arrangement, in which the locking piece 3 is locked, is made in the circular piece 2. The electrode 1 extends to the hole 6 in the electrode structure. According to the figure, the brittle electrode 1 is tightly inside the body structure 2. Figures 5 and 6 show a perspective view of additional details of the invention. Thus, the upper surface of the locking piece 3 is essentially annular in shape and forms a uniform flat surface on the side opposite to the measuring surface.
According to Figure 7, the electrode structures are placed at regular intervals in the cap 7 and the cap is placed around the skull.
The measuring leads of the measuring cap are wound into a tight, preferably spiral bundle, in order to reduce interference. In addition, according to a preferred embodiment of the invention, the earth and reference electrode leads of the measuring cap are wound tightly together, to reduce interference. Interference can be further reduced by running the measuring leads from the electrodes towards the front of cap 11.
Within the scope of the invention, the electrode structure can deviate from a disc-like shape and flat angular and elliptical shapes too are quite possible. The use of curved surfaces between the body 2 and locking 3 pieces achieves a more even locking effect.
According to one preferred embodiment of the invention, the electrode 1 of the electrode structure 10 is so small in size that a cross-section through any plane at all of the electrode 1 will have a surface area of less than 15 mm2, more preferably of less than 4 mm2.
The small size is important, in order to reduce the electrical field caused by induction and the eddy currents arising in the electrode 1.

Claims

Claims:
1. An electrode structure (10) for attachment to a more extensive measuring structure (11), in order to measure electrical responses from the human body, which electrode structure (10) includes a conductive electrode (1), characterized in that
- the electrode (1) is shaped to be thin in the thickness direction of the electrode structure (10), and - the electrode structure (10) is equipped with a hole (6) and the electrode (1) is located at the edge of the hole (6), in such a way that its longitudinal axis is essentially parallel to the plane of the measurement subject.
2. An electrode structure (10) according to Claim 1, characterized in that the electrode (1) is formed from silver/silver-chloride (Ag-AgCl), in order to form electrically stable interfaces between the measurement subject and the measuring electronics.
3. An electrode structure (10) according to Claim 1 or 2, characterized in that the electrode (1) is thiner than 5 mm and most preferably thiner than 2 mm.
4. An electrode structure (10) according to Claim 1, 2, or 3, characterized in that the electrode structure (10) is attached to the measuring structure (11) using a two-part snap- fit mechanism (2, 3).
5. An electrode structure (10) according to any of the above Claims, characterized in that the electrode (1) is connected to the measuring lead (4) with the aid of a wire (5) of pure silver (Ag).
6. An electrode structure (10) according to an of the above Claims, characterized in that the electrode structure (10) is equipped with a hole (6) and the electrode (1) is located at the edge of the hole (6), and that the diameter of the hole (6) is at least 2 mm, most preferably at least 4 mm.
7. An electrode structure (10) according to any of the above Claims, characterized in that the electrode (1) is cylindrical and the longitudinal axis of the electrode (1) is essentially parallel to the plane of the measurement subject.
8. An electrode structure (10) according to any of the above Claims, characterized in that the electrode structure (10) is formed of body part (2), in which a curved opening is formed, and a locking part (3), which locks into the curved opening in the body part (2).
9. An electrode structure (10) according to any of the above Claims, characterized in that the electrode (1) is of a small size, so that a cross-section along any plane whatever of the electrode (1) has a surface area of less than 15 mm2, most preferably of less than 4 mm2.
10. An electrode structure (10) according to any of the above Claims, characterized in that the electrode (1) is manufactured by sintering from a silver/silver-chloride mass (Ag-AgCl).
11. An electrode structure (10) according to any of the above Claims, characterized in that the structure is thinner than 5 mm, most preferably thinner than 2 mm.
12. A measuring cap (11) for measuring electrical responses from the human body, which measuring cap includes one or more electrode structures (10) and electrical leads (4) connected to them for transmitting the measurement results to the measuring equipment, characterized in that the electrode structures (10) are according to any of Claims 1 - 10, or to a combination of them.
13. A measuring cap (11) according to Claim 12, characterized in that the measuring leads are wound into a tight, preferably spiral bundle, in order to reduce interference.
14. A measuring cap (11) according to Claim 12 or 13, characterized in that the earth and reference electrode leads are wound tightly to each other, in order to reduce interference.
15. A measuring cap (11) according to any of the above Claims 12 - 14, characterized in that the measuring leads are ran from the electrodes towards the front of the cap, in order to reduce interference.
16. A method for attaching the silver lead (5) of an electrode (1) to a measuring lead (4), characterized in that the measuring electrode (1), which includes a silver/silver-chloride
(Ag-AgCl) electrode (1) and a silver lead (5) connected to it, is attached to the measuring lead (4) using an electrically conductive connection, for example, by soldering or crimping, forming the electrically conductive connection in such a way that the electrode does not touch the connection point, nor does the electrode touch magnetic material, nor is heat conducted to the electrode to such an extent that the sintered electrode structure will alter.
PCT/FI2004/000687 2003-11-18 2004-11-16 Electrode structure for measuring electrical responses from the human body WO2005048837A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2006540480A JP4510027B2 (en) 2003-11-18 2004-11-16 Electrode structure that measures the electrical response from the human body
CN2004800338277A CN1882281B (en) 2003-11-18 2004-11-16 Electrode structure for measuring human body electric reaction
US10/579,832 US7440789B2 (en) 2003-11-18 2004-11-16 Electrode structure for measuring electrical responses from the human body
EP04798296.2A EP1684630B1 (en) 2003-11-18 2004-11-16 Electrode structure for measuring electrical responses from the human body

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI20031677A FI119172B (en) 2003-11-18 2003-11-18 Electrode construction for measuring electrical responses from a human body
FI20031677 2003-11-18

Publications (1)

Publication Number Publication Date
WO2005048837A1 true WO2005048837A1 (en) 2005-06-02

Family

ID=29558646

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/FI2004/000687 WO2005048837A1 (en) 2003-11-18 2004-11-16 Electrode structure for measuring electrical responses from the human body

Country Status (6)

Country Link
US (1) US7440789B2 (en)
EP (1) EP1684630B1 (en)
JP (1) JP4510027B2 (en)
CN (1) CN1882281B (en)
FI (1) FI119172B (en)
WO (1) WO2005048837A1 (en)

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120213697A1 (en) * 2009-04-21 2012-08-23 Albert Einstein College Of Medicine Of Yeshiva University Versatile nanoparticulate biomaterial for controlled delivery and/or containment of therapeutic and diagnostic material
CA2828240A1 (en) 2011-03-03 2012-09-07 Nexstim Oy Cognitive mapping using transcranial magnetic stimulation
EP2714192B1 (en) 2011-06-03 2021-03-10 Nexstim Oyj Method for combining anatomical connectivity patterns and navigated brain stimulation
PL2714193T3 (en) 2011-06-03 2020-06-29 Nexstim Oyj Method of overlaying nbs functional data on a live image of a brain
US9414759B2 (en) * 2011-12-06 2016-08-16 Imris Inc. Surface electrode design that can be left in place during MR imaging
US8989835B2 (en) 2012-08-17 2015-03-24 The Nielsen Company (Us), Llc Systems and methods to gather and analyze electroencephalographic data
US9320450B2 (en) 2013-03-14 2016-04-26 The Nielsen Company (Us), Llc Methods and apparatus to gather and analyze electroencephalographic data
US9622702B2 (en) 2014-04-03 2017-04-18 The Nielsen Company (Us), Llc Methods and apparatus to gather and analyze electroencephalographic data
CN104224167B (en) * 2014-09-21 2016-06-01 北京师范大学 Disposable brain condition monitoring flexible patch electrode
EP3684463A4 (en) 2017-09-19 2021-06-23 Neuroenhancement Lab, LLC Method and apparatus for neuroenhancement
US11717686B2 (en) 2017-12-04 2023-08-08 Neuroenhancement Lab, LLC Method and apparatus for neuroenhancement to facilitate learning and performance
US11318277B2 (en) 2017-12-31 2022-05-03 Neuroenhancement Lab, LLC Method and apparatus for neuroenhancement to enhance emotional response
US11364361B2 (en) 2018-04-20 2022-06-21 Neuroenhancement Lab, LLC System and method for inducing sleep by transplanting mental states
WO2020056418A1 (en) 2018-09-14 2020-03-19 Neuroenhancement Lab, LLC System and method of improving sleep
US11786694B2 (en) 2019-05-24 2023-10-17 NeuroLight, Inc. Device, method, and app for facilitating sleep
CN112401908B (en) * 2020-12-02 2024-07-19 中国人民解放军海军特色医学中心 Fatigue monitoring device, fatigue monitoring method, computing equipment and storage medium
CN114209418B (en) * 2021-12-13 2023-08-08 宝施医疗用品(深圳)有限公司 Neutral electrode for inductive homogenization current

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4773424A (en) * 1985-10-02 1988-09-27 Fukuda Denshi Co., Ltd. Electrocardiographic electrode
JPH0467841A (en) 1990-07-06 1992-03-03 Terumo Corp Electrode for living body
WO2000027279A1 (en) * 1998-11-10 2000-05-18 Durousseau Donald R fMRI COMPATIBLE ELECTRODE AND ELECTRODE PLACEMENT TECHNIQUES
US6067464A (en) * 1996-10-07 2000-05-23 Brain Functions Laboratory, Inc. Electrode
US6091977A (en) * 1995-04-07 2000-07-18 The University Of Miami Sensor

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3170459A (en) * 1962-03-20 1965-02-23 Clifford G Phipps Bio-medical instrumentation electrode
US3469577A (en) * 1967-03-02 1969-09-30 Beckman Instruments Inc Scalp contacting bioelectrode
US3580240A (en) * 1969-01-17 1971-05-25 Hoffmann La Roche Disposable electrode with self-sealing plug outlet
US4040412A (en) * 1974-08-09 1977-08-09 Sato Takuya R Bioelectrodes
US4051842A (en) * 1975-09-15 1977-10-04 International Medical Corporation Electrode and interfacing pad for electrical physiological systems
US4323076A (en) * 1979-09-12 1982-04-06 Electro-Cap, Inc. Electrode cap
JPS623124Y2 (en) * 1981-03-14 1987-01-24
US4537198A (en) * 1983-05-03 1985-08-27 Sue Corbett Electrode cap
US4580572A (en) * 1983-06-01 1986-04-08 Bio-Stimu Trend Corp. Garment apparatus for delivering or receiving electric impulses
US4709702A (en) * 1985-04-25 1987-12-01 Westinghouse Electric Corp. Electroencephalographic cap
GB8609582D0 (en) * 1986-04-18 1986-05-21 Said Ismail Hakky Blood loss measurement
JPH03656U (en) * 1989-05-24 1991-01-08
JPH0385003U (en) * 1989-12-20 1991-08-28
US5191891A (en) * 1991-09-10 1993-03-09 Ralin, Inc. Portable ECG monitor/recorder
US6445940B1 (en) * 2000-08-11 2002-09-03 Sam Technology, Inc. Ceramic single-plate capacitor EEG electrode
JP2002177231A (en) * 2000-12-18 2002-06-25 Nou Kinou Kenkyusho:Kk Bio-electrode structure and electroencephalogram measuring head gear
US7155276B2 (en) * 2001-07-17 2006-12-26 Lamont John Method and apparatus to modify cranial electrical potentials to remediate psychiatric disorders and to enhance optimal brain functioning

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4773424A (en) * 1985-10-02 1988-09-27 Fukuda Denshi Co., Ltd. Electrocardiographic electrode
JPH0467841A (en) 1990-07-06 1992-03-03 Terumo Corp Electrode for living body
US6091977A (en) * 1995-04-07 2000-07-18 The University Of Miami Sensor
US6067464A (en) * 1996-10-07 2000-05-23 Brain Functions Laboratory, Inc. Electrode
WO2000027279A1 (en) * 1998-11-10 2000-05-18 Durousseau Donald R fMRI COMPATIBLE ELECTRODE AND ELECTRODE PLACEMENT TECHNIQUES

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN *

Also Published As

Publication number Publication date
FI119172B (en) 2008-08-29
JP4510027B2 (en) 2010-07-21
FI20031677A (en) 2005-05-19
EP1684630A1 (en) 2006-08-02
FI20031677A0 (en) 2003-11-18
EP1684630B1 (en) 2014-02-26
US20070106141A1 (en) 2007-05-10
JP2007511309A (en) 2007-05-10
US7440789B2 (en) 2008-10-21
CN1882281B (en) 2011-10-05
CN1882281A (en) 2006-12-20

Similar Documents

Publication Publication Date Title
EP1684630B1 (en) Electrode structure for measuring electrical responses from the human body
Krakow et al. EEG recording during fMRI experiments: image quality
US6708051B1 (en) FMRI compatible electrode and electrode placement techniques
Maccabee et al. An analysis of peripheral motor nerve stimulation in humans using the magnetic coil
Allen et al. Identification of EEG events in the MR scanner: the problem of pulse artifact and a method for its subtraction
JP6746300B2 (en) Neurostimulator, biomagnetic field measurement system
US5097835A (en) Subdural electrode with improved lead connection
JP4805456B2 (en) Electrode and electrode arrangement method suitable for functional magnetic resonance imaging apparatus
US8945090B2 (en) Implantable radiopaque marking
US7294785B2 (en) Patient cable for medical measurements
JPS6462146A (en) Adaptable coil assembly in magnetic imaging apparatus for head or body of a person
WO1999023942A1 (en) Electrocardiographic monitoring during magnetic resonance imaging
Melcher et al. Dependence of the MEG on dipole orientation in the rabbit head
EP3820362B1 (en) Recording electrode for electrophysiological signal measurement
JP2004097590A (en) Probe for somatometry, and probe holder for somatometry
EP2120699B1 (en) Arrangement and method for influencing and/or detecting magnetic particles in a region of action
US20080012568A1 (en) Physiological Sensor System
Lemieux et al. Methodological issues in EEG-correlated functional MRI experiments
US10213615B2 (en) System and method for micromagnetic stimulation of the central nervous system
JP3455856B2 (en) Magnetic detector
KR20040010525A (en) Fetal scalp electrode
JP7460155B2 (en) Brain function measurement device and brain function measurement method
JP2021062100A (en) Brain function measurement apparatus and brain function measurement method
Hoffman et al. Knowledge Transfer from Electrostimulation to Peripheral Nerve Stimulation by Magnetic Gradient Fields in MRI
JPH0975313A (en) Manipulating device for biological signal measurement and brain magnetic field measuring instrument

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 200480033827.7

Country of ref document: CN

AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 2004798296

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2007106141

Country of ref document: US

Ref document number: 10579832

Country of ref document: US

DPEN Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed from 20040101)
WWE Wipo information: entry into national phase

Ref document number: 2006540480

Country of ref document: JP

NENP Non-entry into the national phase

Ref country code: DE

WWW Wipo information: withdrawn in national office

Ref document number: DE

WWP Wipo information: published in national office

Ref document number: 2004798296

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 10579832

Country of ref document: US