WO1991013584A1 - Appareil pour placer des electrodes - Google Patents

Appareil pour placer des electrodes Download PDF

Info

Publication number
WO1991013584A1
WO1991013584A1 PCT/US1991/001260 US9101260W WO9113584A1 WO 1991013584 A1 WO1991013584 A1 WO 1991013584A1 US 9101260 W US9101260 W US 9101260W WO 9113584 A1 WO9113584 A1 WO 9113584A1
Authority
WO
WIPO (PCT)
Prior art keywords
electrodes
subject
fetal
light sources
flicker
Prior art date
Application number
PCT/US1991/001260
Other languages
English (en)
Inventor
Andrew L. Pearlman
Original Assignee
Srd Shorashim Medical, Ltd.
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 Srd Shorashim Medical, Ltd. filed Critical Srd Shorashim Medical, Ltd.
Publication of WO1991013584A1 publication Critical patent/WO1991013584A1/fr

Links

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/68Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient
    • A61B5/6801Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient specially adapted to be attached to or worn on the body surface
    • A61B5/6813Specially adapted to be attached to a specific body part
    • A61B5/6814Head
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/103Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes
    • A61B5/11Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb
    • A61B5/1103Detecting eye twinkling
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/16Devices for psychotechnics; Testing reaction times ; Devices for evaluating the psychological state
    • A61B5/161Flicker fusion testing
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/16Devices for psychotechnics; Testing reaction times ; Devices for evaluating the psychological state
    • A61B5/163Devices for psychotechnics; Testing reaction times ; Devices for evaluating the psychological state by tracking eye movement, gaze, or pupil change
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/25Bioelectric electrodes therefor
    • A61B5/279Bioelectric electrodes therefor specially adapted for particular uses
    • A61B5/28Bioelectric electrodes therefor specially adapted for particular uses for electrocardiography [ECG]
    • A61B5/282Holders for multiple electrodes
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/25Bioelectric electrodes therefor
    • A61B5/279Bioelectric electrodes therefor specially adapted for particular uses
    • A61B5/28Bioelectric electrodes therefor specially adapted for particular uses for electrocardiography [ECG]
    • A61B5/283Invasive
    • A61B5/288Invasive for foetal cardiography, e.g. scalp electrodes
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/25Bioelectric electrodes therefor
    • A61B5/279Bioelectric electrodes therefor specially adapted for particular uses
    • A61B5/291Bioelectric electrodes therefor specially adapted for particular uses for electroencephalography [EEG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/25Bioelectric electrodes therefor
    • A61B5/279Bioelectric electrodes therefor specially adapted for particular uses
    • A61B5/297Bioelectric electrodes therefor specially adapted for particular uses for electrooculography [EOG]: for electroretinography [ERG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/30Input circuits therefor
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/30Input circuits therefor
    • A61B5/302Input circuits therefor for capacitive or ionised electrodes, e.g. metal-oxide-semiconductor field-effect transistors [MOSFET]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/30Input circuits therefor
    • A61B5/307Input circuits therefor specially adapted for particular uses
    • A61B5/308Input circuits therefor specially adapted for particular uses for electrocardiography [ECG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/30Input circuits therefor
    • A61B5/307Input circuits therefor specially adapted for particular uses
    • A61B5/31Input circuits therefor specially adapted for particular uses for electroencephalography [EEG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/30Input circuits therefor
    • A61B5/307Input circuits therefor specially adapted for particular uses
    • A61B5/313Input circuits therefor specially adapted for particular uses for electromyography [EMG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/30Input circuits therefor
    • A61B5/307Input circuits therefor specially adapted for particular uses
    • A61B5/315Input circuits therefor specially adapted for particular uses for electrooculography [EOG]; for electroretinography [ERG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/316Modalities, i.e. specific diagnostic methods
    • A61B5/389Electromyography [EMG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/316Modalities, i.e. specific diagnostic methods
    • A61B5/398Electrooculography [EOG], e.g. detecting nystagmus; Electroretinography [ERG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/43Detecting, measuring or recording for evaluating the reproductive systems
    • A61B5/4306Detecting, measuring or recording for evaluating the reproductive systems for evaluating the female reproductive systems, e.g. gynaecological evaluations
    • A61B5/4343Pregnancy and labour monitoring, e.g. for labour onset detection
    • A61B5/4362Assessing foetal parameters
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/02Details
    • A61N1/04Electrodes
    • A61N1/0404Electrodes for external use
    • A61N1/0408Use-related aspects
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/02Details
    • A61N1/04Electrodes
    • A61N1/0404Electrodes for external use
    • A61N1/0472Structure-related aspects
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2503/00Evaluating a particular growth phase or type of persons or animals
    • A61B2503/02Foetus
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2560/00Constructional details of operational features of apparatus; Accessories for medical measuring apparatus
    • A61B2560/04Constructional details of apparatus
    • A61B2560/0487Special user inputs or interfaces
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2562/00Details of sensors; Constructional details of sensor housings or probes; Accessories for sensors
    • A61B2562/02Details of sensors specially adapted for in-vivo measurements
    • A61B2562/0209Special features of electrodes classified in A61B5/24, A61B5/25, A61B5/283, A61B5/291, A61B5/296, A61B5/053
    • A61B2562/0214Capacitive electrodes
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2562/00Details of sensors; Constructional details of sensor housings or probes; Accessories for sensors
    • A61B2562/16Details of sensor housings or probes; Details of structural supports for sensors
    • A61B2562/166Details of sensor housings or probes; Details of structural supports for sensors the sensor is mounted on a specially adapted printed circuit board
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2562/00Details of sensors; Constructional details of sensor housings or probes; Accessories for sensors
    • A61B2562/24Hygienic packaging for medical sensors; Maintaining apparatus for sensor hygiene
    • A61B2562/247Hygienic covers, i.e. for covering the sensor or apparatus during use
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/68Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient
    • A61B5/6801Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient specially adapted to be attached to or worn on the body surface
    • A61B5/6802Sensor mounted on worn items
    • A61B5/6803Head-worn items, e.g. helmets, masks, headphones or goggles
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/68Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient
    • A61B5/6801Arrangements of detecting, measuring or recording means, e.g. sensors, in relation to patient specially adapted to be attached to or worn on the body surface
    • A61B5/6813Specially adapted to be attached to a specific body part
    • A61B5/6814Head
    • A61B5/6821Eye
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/72Signal processing specially adapted for physiological signals or for diagnostic purposes
    • A61B5/7203Signal processing specially adapted for physiological signals or for diagnostic purposes for noise prevention, reduction or removal
    • A61B5/7207Signal processing specially adapted for physiological signals or for diagnostic purposes for noise prevention, reduction or removal of noise induced by motion artifacts
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/72Signal processing specially adapted for physiological signals or for diagnostic purposes
    • A61B5/7235Details of waveform analysis
    • A61B5/725Details of waveform analysis using specific filters therefor, e.g. Kalman or adaptive filters
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/02Details
    • A61N1/04Electrodes
    • A61N1/0404Electrodes for external use
    • A61N1/0408Use-related aspects
    • A61N1/0452Specially adapted for transcutaneous muscle stimulation [TMS]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/02Details
    • A61N1/04Electrodes
    • A61N1/0404Electrodes for external use
    • A61N1/0408Use-related aspects
    • A61N1/0456Specially adapted for transcutaneous electrical nerve stimulation [TENS]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/02Details
    • A61N1/04Electrodes
    • A61N1/0404Electrodes for external use
    • A61N1/0472Structure-related aspects
    • A61N1/0476Array electrodes (including any electrode arrangement with more than one electrode for at least one of the polarities)
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/02Details
    • A61N1/04Electrodes
    • A61N1/0404Electrodes for external use
    • A61N1/0472Structure-related aspects
    • A61N1/0484Garment electrodes worn by the patient
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/02Details
    • A61N1/04Electrodes
    • A61N1/0404Electrodes for external use
    • A61N1/0472Structure-related aspects
    • A61N1/0492Patch electrodes

Definitions

  • the present invention relates generally to apparatus for the rapid placement of electrodes on and acquisition of signals from the human body.
  • bioelectric signals from the brain, eyes, muscles or nerves or from a combination of the abovementioned body parts.
  • Other biosignals such as electrodermal signals, heart pulse, voice signals, etc., are often also
  • U.S. Patent 3,882,846 describes a capacitive electrode for acquiring electrocardiographic (ECG) signals which does not necessitate the use of conductive gels or the preparation of the skin of a subject before acquiring the ECG signals. While a major improvement in the practicality of ECG signal acquisition, the
  • apparatus for mounting electrodes on a human body which apparatus is operative to obtain human biosignals and comprises close fitting clothing apparatus, a plurality of electrodes mounted to the close fitting clothing apparatus, removable cover sheet apparatus for providing a sterile interface between the skin and at least one of the electrodes and joining apparatus for joining the cover sheet apparatus to at least one of the plurality of electrodes.
  • the apparatus for mounting electrodes on a human body also comprises signal processing apparatus mounted on the close fitting clothing apparatus for preamplifying, transient protecting and filtering at least one differential signal obtained between two of the electrodes.
  • the cover sheet apparatus includes reference apparatus for providing a reference signal for at least one of the plurality of electrodes.
  • the cover sheet apparatus includes conductive apparatus for providing a conductive path between at least one of the plurality of electrodes and the human body.
  • At least one of the plurality of electrodes is a capacitive electrode.
  • the close fitting clothing apparatus can be a glove, a face mask, goggles, a headband, glasses, a cap or a pilot flight helmet. If the close fitting apparatus is a glove, a
  • photoplethysmographic sensor may be included.
  • a referenced capacitive electrode assembly for mounting on human skin comprising a capacitive electrode mounted in a
  • sterilizable removable cover apparatus separate from the capacitive electrode for providing an electrical reference signal and for providing a
  • the sensor channel comprises a set of at least two capacitive electrodes mounted in a substrate, removable cover apparatus separate from the set of capacitive electrodes for providing a separable interface between the human skin and at least one of the capacitive electrodes and including reference apparatus for providing an electrical reference signal for the sensor channel, joining apparatus for joining the cover apparatus to the capacitive electrodes and signal processing apparatus for processing the bioelectric signals.
  • capacitive electrode for mounting on human skin and comprising a housing having a skin-facing side in which there is an opening, a conductive element placed in the opening and lying along the skin-facing side, and a dielectric cover covering the opening and touching the conductive element.
  • apparatus for alerting a drowsing subject comprising a close fitting frame mounted on the subject's head, a plurality of electrodes mounted to the close fitting frame for measuring biosignal activity occurring
  • data processing apparatus for processing the biosignal activity into baseline curves and for
  • the biosignals can be of high and/or low frequency and the apparatus includes response detection means for detecting the subject's response to an alert issued by the alerting apparatus.
  • the alerting apparatus includes apparatus for producing a variety of audible sounds.
  • the alerting apparatus also includes apparatus for varying the intensity of the audible sounds.
  • a head motion sensor for detecting head motion is also optionally included in the apparatus for alerting a drowsing subject.
  • the close fitting frame is a frame of a pair of eyeglasses, a set of goggles, a headband or a frame of a face mask.
  • a method of alerting a drowsing subject including the steps of receiving biosignals from electrodes placed on and near the face of the subject, processing the biosignals into baseline curves, and determining when amplitudes of the biosignals cross the baseline curves for longer than a predetermined amount of time indicating an increased risk of drowsiness, alerting the subject via an alerting action every time the increased risk of drowsiness is indicated, and detecting a response to the alerting action.
  • the alerting action differs each time the increased risk of drowsiness is indicated.
  • the alerting action is an audible sound whose intensity is initially low and intensifies until the subject gives a confirmatory response indicating that the subject is alert.
  • apparatus for rapidly preparing to obtain biosignals from a human body comprising close fitting clothing apparatus, a plurality of electrodes mounted to the close fitting clothing apparatus, wherein at least one of the
  • Electrodes is a capacitive electrode and reference apparatus mounted to the close fitting clothing
  • apparatus for providing a reference signal for use together with the at least one capacitive electrode.
  • a fetal biosignal probe for rapidly obtaining biosignals of a fetus, typically during labor, comprising at least one capacitive electrode apparatus mounted on a flexible body for obtaining fetal biosignals and referencing apparatus for providing a reference signal for the capacitive electrode apparatus.
  • a system for rapidly obtaining fetal biosignals comprising at least two fetal biosignal probes to be temporarily attached to a fetus scalp and signal processing apparatus for processing fetal electroen ⁇ ephalographic signals.
  • apparatus and a method for measuring a critical flicker fusion frequency of a subject comprising a plurality of light sources arranged in a predetermined pattern, typically familiar to a subject, comprising a first multiplicity of
  • background light sources and a second multiplicity of flicker group light sources driving circuitry apparatus for illuminating the background light sources so as to appear non-flickering, for oscillating the flicker group light sources at a gradually decreasing oscillation frequency and for maintaining the background and flicker group light sources visually indistinguishable, and input apparatus operated by the subject for indicating to the driving circuitry apparatus at which frequency flicker is first observed in the flicker group and which of the plurality of light sources belongs to the flicker group.
  • Fig. 1A is an isometric illustration of an electrode assembly and a cover sheet assembly covering the electrode assembly constructed and operative in accordance with an embodiment of the present invention
  • Fig. 1B is a side view sectional illustration of the electrode and cover sheet assemblies of Fig. 1A;
  • Figs. 1C and 1D are side view sectional illustrations of alternative embodiments of the
  • Fig. 2 is a side view sectional illustration of an electrode assembly and an alternative embodiment of the cover sheet assembly of Fig. 1B useful for incorporating conductive lubrication means;
  • Fig. 3A is a schematic illustration of a face mask having any one of the electrode assemblies of Fig. 1 and two sterile integrated electrode covers
  • FIG. 3B is a detailed schematic illustration of one of the sterile integrated electrode covers of Fig. 3A;
  • Fig. 4 is a schematic illustration of an alternate embodiment of the face mask of Fig. 3 in conjunction with a flexible printed circuit
  • Fig. 5 is a detailed schematic illustration of the flexible printed circuit of Fig. 4;
  • Fig. 6 is an electronic schematic diagram of a circuit for preamplification, transient protection and filtering of bioelectric signals
  • Fig. 7A is a pictorial illustration of a cap in which are incorporated the electrode assemblies of Fig. 2;
  • Figs. 7B and 7C are pictorial illustrations of a pilot flight helmet into which are incorporated capacitive electrodes;
  • Fig. 8 is a pictorial illustration of a glove in which are incorporated any one of the electrode assemblies of Fig. 1;
  • Figs. 9A, 9B and 9C are pictorial
  • Figs. 10A and 10B are graphic illustrations of RMS amplitude curves of low and high frequency signals produced by the apparatus of Figs. 9A - 9C;
  • Fig. 11 is a block diagram illustration of processing apparatus useful in the apparatus of
  • Fig. 12 is a schematic circuit diagram of a signal conditioning module useful in the processing means of Fig. 11;
  • Fig. 13 is a schematic illustration of
  • Figs. 14A, 14B and 14C are front, back and side view illustrations of a fetal biosignal probe utilizing the electrodes of Fig. 1;
  • Figs. 15A, 15B and 15C are front, back and side view illustrations of an alternative embodiment of a fetal biosignal probe utilizing the electrodes of Fig. 1;
  • Fig. 16 is a part pictorial, part block diagram illustration of a system for obtaining fetal biosignals during delivery using one or both of the fetal biosignal probe of Figs. 14 and 15;
  • Fig. 17 is a part pictorial, part block diagram illustration of apparatus for measuring Critical Flicker Fusion.
  • Fig. 18 is an electronic schematic of circuitry forming part of the apparatus of Fig. 17.
  • Electrode assembly 10 typically comprises a capacitive electrode 14, such as those available from Heart Rate Inc. of Costa Mesa, Ca.
  • Electrode assembly 10 additionally comprises a flexible non-conducting substrate 16, such as silicone rubber or soft plastic, in which is mounted capacitive electrode 14. Also mounted in substrate 16, near electrode 14, is at least one electrical contact site, shown in Fig. 1B as two contact sites 18 and 20.
  • electrical conductors 22 Attached to electrical contact sites 18 and 20 and to electrode 14, and passing through or residing within substrate 16, are electrical conductors 22.
  • Electrical conductors 22 terminate at an electrical connector 24.
  • Cover sheet assembly 12 is typically a thin sheet which is typically disposable but may
  • Fig. 1B typically comprises at least one electrical contact medium, shown in Fig. 1B as contact media 26 and 28, for touching human skin and for providing an electrical reference signal to electrode 14.
  • Media 26 and 28 are typically conductive silver impregnated cloth electrodes, such as the E301 or E331 electrodes manufactured by In-Vivo Metric of Healdsburg, Ca., and are typically mounted on a non-conductive substrate 30, such as a thin plastic sheet. Through openings in substrate 30, media 26 and 28 are
  • the metallic contacts 32 and 34 are designed to easily and removably attach but firmly to contact sites 18 and 20, thereby providing a reference signal for electrode 14.
  • a pair of one contact site 18 or 20 and one metallic contact 32 or 34 creates both a mechanical and an electrical connection between the cover sheet assembly 12 and the electrode assembly 10.
  • An appropriate pair is a male-female press contact pair such as the Dot contact manufactured by TRW Corporation of the USA.
  • the pair can be formed of silver
  • the mechanical joining and the electrical joining can be produced separately by two separate connection assemblies.
  • An example of such a dual joining assembly is an adhesive band around the border of cover 12 on the side of substrate 30 which is not in contact with the skin for mechanical joining and a separate Dot contact pair inside the border for electrical joining.
  • Electrode assembly 40 An alternate embodiment of electrode assembly, labeled 40, is shown in Fig. 2 and is intended for use, in conjunction with a cover sheet assembly 42, on areas covered by body hair.
  • Cover sheet assembly 42 comprises a substrate 44, preferably made of a thin plastic film, and a multiplicity of sponges 46 filled with a moist conductive gel or similar conductive medium and attached to the substrate 44.
  • a protective, sealing cover film 48 such as is used in commercial disposable ECG electrodes such as the Red Dot electrode manufactured by 3M Corporation of Minnesota, USA, maintains the gel in sponge 46 in a wetted state and is typically peeled from the cover 42 after the cover 42 is attached to electrode 14.
  • cover sheet assembly 42 additionally comprises contact media 26 and 28 and metallic contacts 32 and 34 for providing a reference signal for electrode 14.
  • electrode assembly 40 comprises a substrate 50, similar to
  • Cover sheet assembly 42 is attached to substrate 50 via adhesive pads 52 such that sponges 46 lie on top of electrode 14 and media 26 and 28.
  • adhesive pads 52 can be made of Velcro (registered trademark).
  • sponge 46 provides a moist electrical connection between the skin and substrate 44.
  • Substrate 44 may optionally have pores under sponge 46 to establish electrical contact with electrode 14 and media 26 and 28.
  • the sealing cover film 48 is made to hermetically seal off all sides of cover 42 so as to preserve the moistness of sponges 46. Sealing cover film 48 is similar to those used for disposable ECG electrodes.
  • the electrode apparatus 10 or 40 is first covered by its respective cover sheet assembly 12 or 42 and then the combination is placed onto the skin of a subject, with the cover assembly side located against the skin. Via the electrode and cover sheet assembly combination, reference and bioelectric signals are gathered, without the necessity of skin preparation. Due to the
  • electrode assemblies 10 and 40 are hygienic and suitable for sterile use with a multiplicity of subjects.
  • FIG. 1C and 1D illustrate alternative embodiments of electrode assembly 40 in which a single dielectric layer separates the skin from the conductive element of the capacitive electrode 14.
  • the capacitive electrode here denoted 60, comprises a conductive element 62, such as a piece of metal, a dielectric material 64, such as a thin plastic sheet, forming a cover to a three-sided housing 66, and a buffer amplifier 68.
  • Capacitive electrode 60 performs as a capacitor after being mounted, dielectric material 64 side down, onto the human skin.
  • Buffer amplifier 68 operates in a manner similar to the buffer amplifier in U.S. Patent 3,882,846. It is operative on the signal detected by the combination of the conductive element 62 and the dielectric material 64.
  • the conductive element 62 and the buffer amplifier 68 are enclosed within housing 66 which is covered by dielectric material 64.
  • Conductive element 62 is placed inside housing 66 in a location close to the side of housing 66 which is covered by dielectric material 64. In this manner, conductive element 62 touches dielectric material 64.
  • the dielectric material 64 can be formed as an integral part of housing 66, as shown in Fig. 1C, or as a detachable element, as shown in Fig. 1D. In the embodiment of Fig. 1D, the
  • dielectric material 64 operates both as a dielectric and as the substrate of cover sheet assembly 12 of Fig. 1B.
  • capacitive electrodes 60 of Figs. 1C and 1D can be utilized in place of capacitive electrode 14 in the assembly of Fig. 1B.
  • Capacitive electrode 60 is advantageous over capacitive electrode 14 in that capacitive electrode 14 typically has two dielectric layers, one inside the electrode housing and one defining substrate 30, while capacitive electrode 60 has only one dielectric layer 64 which serves both as a dielectric and as a cover sheet assembly.
  • FIGs. 3A, 3B, 4 and 5 illustrate apparatus 70, constructed and operative in accordance with a preferred embodiment of the present invention, for rapidly applying electrodes, such as any of the electrodes of Fig. 1, to the face of a subject.
  • Apparatus 70 requires no skin or electrode preparation, nor does it require much knowledge on the part of the operator as to the correct placement of the electrodes. It is designed to be easy for an unskilled operator to use and to be comfortable and hygienic for a subject to wear.
  • apparatus 68 is typically
  • a face mask 70 including a pair of frames 71, similar to the frames of swimmer's goggles and typically manufactured of a soft material such as silicone rubber or a soft plastic, an adjustable bridge 72 for enabling the face mask 70 to adapt to the
  • an adjustable band 74 typically an elastic band, for firmly maintaining the face mask 70 against the face of a subject.
  • the adjustability of the adjustable band 74 accommodates subjects with different head sizes.
  • a multiplicity of electrode assemblies such as apparatus 10 (Figs. 1A and 1B), labeled 10a - 10j, for receiving facial
  • the electrode assemblies 10a - 10j are located in predetermined locations around the eyes so as to measure biosignals relating to eye movement and eye position. Specifically, electrodes 10a and 10b are located in frame 71 so as to be above a subject's pupils and electrodes 10g and 10h are arranged so as to be located below the subject's pupils. Electrodes 10e and 10f are located so as to be placed in the inner canthus of the eyes and electrodes 10j and 10i are located so as to be placed in the outer canthi of the eyes.
  • Electrodes 10c and 10d are arranged to be located at the temples and are therefore placed on adjustable band 72.
  • Typical biosignals to be measured are as follows: electrode pairs 10a and 10g and 10b and 10h measure electrooculograms (EOGs) relating to the
  • electrode pairs 10j and 10e and 10f and 10i measure EOGs relating to the horizontal motion and position of the left and right eyes, respectively.
  • electrodes 10e and 10f may be replaced by a single electrode at 10e, at 10f, on the nose bridge, or between the eyebrows.
  • the horizontal and vertical motion measurements are useful for detecting nystagmus and for measuring a subject's blink response and the convergence capability of a subject's eyes.
  • Electrodes 10a and 10b, located above the pupils, are also useful for measuring the electromyogram (EMG) of facial muscles and electrodes 10c and 10d are useful for measuring EMGs of muscles associated with eye lids and eye movements or with facial relaxation.
  • EMG electromyogram
  • the cover sheet assemblies 12 corresponding to the multiplicity of electrodes 10a - 10j are formed in two integrated cover sheet assemblies 76 and 78.
  • Covers 76 and 78 are designed so as to cover all of the portions of face mask 70 which come into contact with the skin of a subject, including the temples and the areas near the inner canthi of the eyes. They are replaceable so as to ensure that apparatus 70 is hygienic and can be used with a multiplicity of subjects without concern of spreading disease from one subject to the next.
  • Cover sheet assembly 78 is shown in detail in
  • Cover sheet assembly 78 includes substrate 30 onto which are placed one or more media 26 and 28, where, for clarity's sake, only one pair of media 26 and 28 are shown. Media 26 and 28 are arranged on substrate 30 such that they will mate with the corresponding electrode assembly 10 located on face mask 70.
  • electrode assemblies 10 are connected to signal processing equipment via electrical connections 80 (Fig. 5), typically comprised of wires.
  • electrical connections 80 typically comprised of wires.
  • electrode assemblies 10 and their respective electrical connections 80 are embedded in flexible printed circuits 82 (Figs. 4 and 5) which are fixedly or removably attached to face mask 70 and extend along adjustable band 74.
  • the electrical connections 80 typically terminate at a single connector 84 located on the face mask 70 or within a cable 86 which extends from the face mask 70.
  • Flexible printed circuits 82 can be molded directly onto face mask 70. Alternatively, they can be formed into a soft plastic ribbon or otherwise
  • the soft plastic ribbon can then be removably mounted to face mask 70 using renewable adhesive pads or other renewable binding means.
  • preamplification, transient protection and bandpass filtering circuits are associated with face mask 70 for each pair of electrode assemblies 10 attached to face mask 70.
  • the circuits for the entirety of the pairs of electrode assemblies 10 corresponding to each eye are preferably incorporated as a hybrid circuit in signal processors 88 and 90 attached to frame 71.
  • signal processors 88 and 90 By attaching signal processors 88 and 90 to the frame 71, noise pickup caused by cabling is reduced.
  • a reference signal is provided for common mode
  • a reference electrode 92 preferably comprised of a silver impregnated cloth electrode, such as the E301 or E331 electrode
  • signal processing equipment is typically provided with face mask 70. It typically comprises a power supply 94 for supplying the required voltages to the electrode assemblies 10 of the face mask 70 and amplifiers 96 for further conditioning and processing of the preamplified biosignals received from signal processors 88 and 90. Specifically, the electrode assembly 10 and the signal processors 88 and 90 normally require power in the 10 - 500 milliwatt range.
  • digital circuitry 98 may occur in digital circuitry 98. It will be appreciated that power supply 94, amplifiers 96 and digital circuitry 98 are typically located separately from face mask 70. It will also be appreciated that power supply 94, amplifiers 96 and digital circuitry 98 are typically located separately from face mask 70. It will also be
  • single connector 84 enables face mask 70 to be readily and easily separatable from the signal processing equipment.
  • Fig. 5 details elements of one of the flexible printed circuit boards 82. Shown are the electrical connections 80 which bring the voltage from power supply 94 to the electrode assembly 10 and bring to the amplifiers 96 the desired differential biosignals from signal processor 88. Specifically, connections 80a and 80b provide voltage to the electrode assembly 10 and to the signal processor 88, connection 80c connects to reference electrode 92, and connections 80d and 80e provide preamplified, filtered signals from the two pairs of electrode assemblies 10. In order to obtain a differential signal between the pair of electrodes 10c and 10d on the temples, the two connections 80f are both connected to connector 84. Connections 80f are connected to
  • Electrodes 10c and 10d are located on the respective flexible printed circuit boards 82.
  • the differential signal is then typically created in one of signal processors 88 and 90.
  • the section of flexible circuit board 82 on which lies electrode 10e is preferably bent in order to match the curvature of the area between the eye and the nose bridge.
  • Fig. 6 illustrates a typical circuit for preamplification, transient protection and bandpass filtering of a single differential signal acquired from a pair of electrodes and a reference electrode.
  • the circuit is believed to be self-explanatory and therefore, in the interest of conciseness, a full description will not be given. It will be noted that the components are selected to provide low and high frequency cutoffs at predetermined frequencies, such as 0.5 and 200 Hz.
  • processors 88 and 90 typically contain at least one circuit such as is shown in Fig. 6.
  • face mask 70 is utilized as follows. Preparatory to placing the face mask 70 on a subject's face, an operator attaches cover sheet assemblies 76 and 78 to face mask 70 by snapping together the contact pairs 18 and 32 and 20 and 34.
  • the mask 70 is then placed onto the subject's face, and the adjustable bridge 71 is adjusted, if necessary. Finally, connector 84 is attached to cables connected to the signal processing equipment.
  • the electrode assemblies 10 are in their proper location and are now ready to obtain measurements. No further adjustments are required. In this manner, the
  • Electrodes are placed on a subject with ease.
  • the apparatus 70 can be utilized for determining a vertical and/or horizontal gaze position relative to the position of the head.
  • the horizontal and vertical components of the three-dimensional gaze angle defined here as the horizontal and vertical gaze
  • the relationship between the gaze position and the amplitude of the EOG signal is obtained by having the subject observe targets at known angular positions relative to "straight ahead" as is common practice in neurological tests of EOG and eye movements.
  • the vertical EOG is obtained from a pair of electrodes, illustrated in Fig. 5 as 10a and 10g or 10b and 10h, which are typically located above and below one eye, respectively.
  • the horizontal EOG is obtained from the pair of electrodes 10g and 10i which are typically placed near the outer canthus of each eye.
  • the gaze position can be utilized in an eye mouse, an apparatus for providing one or two-dimensional positional input to a computer, providing much the same information as that provided by a mechanical mouse.
  • the eye mouse is utilized as follows: while keeping his head fixed, a subject calibrates the eye mouse by looking at a predetermined calibration position on the computer screen or within his field of view and by confirming through some standard input route, such as via a keyboard or a mechanical mouse button, that he is looking at the calibration position known to the
  • Computer software implementing equations 1 - 6 hereinbelow, receives the horizontal and vertical EOG amplitudes, after low pass filtering by digital
  • circuitry 98 to remove transients and sudden jerks or other high frequency noises or artifacts, and associates them with the predetermined calibration position.
  • the computer software receives the EOG amplitudes for the second point and computes from them, from the first EOG amplitudes, and from the coordinates of the two calibration points, a relationship between the subject's horizontal and vertical EOG amplitudes, EX and EY respectively, and the position X, Y of a point at which the subject is gazing for a given distance and orientation of the head relative to the computer screen.
  • the X, Y position of the point is typically a linear function of the EOG amplitudes EX and EY as follows:
  • Y AY*EY + BY (2)
  • AX, AY, BX and BY are defined as follows:
  • BY Y1 - AY*EY1 (6) and where (X1, Y1) and (X2, Y2) are the computer coordinates of the respective calibration points. X2 is different from X1 and Y2 is different from Y1. EX1 and EX2 are the horizontal EOG amplitudes received when the subject looked at points (X1, Y1) and (X2, Y2) and EY1 and EY2 are the vertical EOG amplitudes received when the subject looked at points (X1, Y1) and (X2, Y2).
  • the subject can look sequentially at the points of a grid or other set (X1, Y1), (X2, Y2), ..., (Xn, Yn), known to the computer, with each point having an
  • any position (X, Y) can be estimated from the measured (EX, EY) of an arbitrary point as long as the subject's head maintains a fixed orientation and
  • the subject upon moving his head, the subject indicates to the computer by keypad or similar input means that his head is being repositioned.
  • the subject indicates via the above means that he is ready for the computer to redefine the new position.
  • the computer sequentially displays one or more points, generally fewer than in the original calibration set, and the subject sequentially moves only his eyes to focus on the most recent point thereby to indicate to the computer when each point is in view. If the subject has not rotated his head or moved it substantially (i.e. the mapping of the eye position to the computer position is basically the same but the offset BX, BY has
  • the eye mouse can be utilized for indicating position information to the computer.
  • the eye mouse remains calibrated only as long as the subject's head remains in a constant position relative to the screen.
  • FIG. 7A illustrates alternative embodiments of the present invention for use in easily acquiring brain, eye, scalp muscle and facial activity signals.
  • Fig. 7A illustrates alternative embodiments of the present invention for use in easily acquiring brain, eye, scalp muscle and facial activity signals.
  • electrode apparatus such as electrode assemblies 40
  • EEG electroencephalograph
  • the electrode assemblies 40 are located along the midline of the skull wherein electrode assemblies 40d and 40e are at the central and occipital regions, respectively, and
  • electrode assemblies 40a, 40b and 40c are on the
  • Electrode assemblies 40i and 40j are held against the skin in the areas behind the ears via extensions of the cap element 100.
  • a reference electrode 41 is preferably located on the forehead.
  • electrode assembly 40 are placed at a multiplicity of points on the skull corresponding to the international 10 - 20 system of EEG electrode placement.
  • the output of the electrode assembly 40 can be utilized, for example, in standard commercial polygraphic stripchart or brain mapping analysis
  • Either electrode placement configuration incorporated alternatively into a close-fitting pilot flight helmet as shown in Fig. 7B and described in more detail hereinbelow, can be used to detect the pilot's EEG, EOG and EMG signals.
  • Such an apparatus can be utilized for detecting changes in pilot status such as loss of consciousness.
  • the electrode assembly 40 are typically mounted to the cap element 100 via an appropriately shaped flexible printed circuit (not shown).
  • an integrated cover sheet assembly of the type shown in Fig. 2, can be utilized; the integrated cover sheet assembly in this embodiment would be a single skull cap composed of a multiplicity of cover sheet assemblies 42.
  • Cap 100 is adjustable to ensure that it firmly fits to any size head.
  • Fig. 7B illustrates the apparatus of the present invention embedded in a pilot flight helmet 102.
  • the apparatus comprises a plurality of capacitive electrodes 14 ranged about the face of a subject, with or without the use of a cover sheet assembly.
  • reference electrode 104 such as a silver impregnated cloth electrode, provides a reference signal for the apparatus and is typically located near the subject's forehead.
  • Flexible wires 106 extend from the electrodes to an internal wiring connector 108, typically placed inside the helmet 102.
  • a pre-amplifier can be included in wiring connector 108 and the output of the connector 108 is typically connected to circuitry (not shown) such as that shown in Fig. 4.
  • a microphone outlet 110 is typically included in such flight helmets and is
  • a pilot flight helmet typically comprises a helmet and padding (not shown) covered by a typically leather liner 112.
  • a plurality of access holes 114 are cut into the liner 112 of the helmet 102 and capacitive electrodes 14 are placed into them.
  • Reference electrode 104 is attached to the skin-side of liner 112 and its connecting wiring is passed through a small hole (not shown) in liner 112 towards internal wiring connector 108.
  • An individual cover sheet assembly 116 can be placed over each capacitive electrode 14, or a single cover sheet assembly 118 can be placed over a plurality of capacitive electrodes 14.
  • the covers 116 and 118 are operative to keep sweat and dirt away from the
  • the padding which is covered by liner 112 can be augmented by, or replaced by, padding of appropriate shape and thickness which already
  • FIG. 8 illustrates another alternate embodiment of the present invention for use in easily acquiring spontaneous or evoked muscle activity signals, as well as
  • the apparatus for rapidly applying electrodes comprises a modified glove 120 onto which are mounted, via the elements described
  • two standard conductive electrodes 122 such as the silver impregnated cloth electrode
  • a photopletheysmographic sensor 124 such as a light source and photodiode combination found in the Model 6390 Omni-Sat ear sensor by Critikon of Tampa, Fl. of the USA, for providing blood flow data.
  • This apparatus is useful for measuring neuromuscular transmission across the wrist, in order to determine deliberate muscle relaxation during surgery or intensive care, while simultaneously monitoring relative blood flow in the finger.
  • glove 120 is elastic and has an adjustable band on the back to ensure that it fits firmly to any size hand.
  • a further embodiment of the present invention is useful for detecting and responding to drowsiness, or pre-sleep behavior, of a subject.
  • electrode assemblies 10 are typically mounted on a frame 131 whose function is similar to that of frame 71.
  • the electrode assemblies 10q - lot are located near the outer canthi of the eyes, temples and/or below the eyes for measuring the EOG and other eye-related signals.
  • the electrode assemblies 10q - lot are typically located as close to the eyes as comfortably possible, preferably without restricting the subject's visual field.
  • a reference electrode 132 such as a silver impregnated cloth electrode manufactured by In-Vivo Metric, is also mounted onto frame 131.
  • electrode 10q can be located behind the ear of the side of the head opposite to electrode lot, which may be located anywhere around the eye or forehead.
  • Frame 131 can be any close fitting frame or clothing which can place a plurality of electrode assemblies near the eyes.
  • a minimal set of electrode assemblies includes one above one eye, one at a
  • Such frames are: an eyeglass frame, a face mask, a cap, goggles, a headband or headphones.
  • Apparatus 130 optionally comprises head motion sensors 134a and 134b. These can be electrodes such as the E220 silver/silver-chloride electrodes manufactured by In-Vivo Metric or any standard metallic electrode type, and are used in conjunction with signal
  • head motion sensors 134a and 134b can be accelerometric motion detectors, used in conjunction with appropriate signal conditioning
  • Head sensors 134a and 134b are mounted on frame 131 in a location which ensures that they are not in contact with the subject's skin, thereby ensuring that they do not pick up any bioelectric signals but instead, measure only head motion.
  • the biosignals and optional head motion signals are collected via flexible circuit boards 136, one of which is shown in Fig. 13, which are similar to the ones described hereinabove with reference to Fig. 5.
  • Flexible circuit boards 136 can be fixedly or removably attached to the frame 131, as described hereinabove. Typically, if frame 131 is the subject's eyeglasses, the flexible circuit boards 136 are removably attached.
  • the signals are sent, via a cable 138, to processing means 140, described in more detail
  • An integrated cover sheet assembly (not shown) is also optionally included.
  • Apparatus 130 is typically utilized for passively and non-obtrusively monitoring a subject for signs of drowsiness. Such an apparatus can be used for monitoring truck drivers or other personnel in jobs in which they must not fall asleep.
  • the processing means 140 comprise a detector module 142 for detecting behavior associated with an increased risk of falling asleep, known hereinafter as the drowsiness condition, and an alerting module 144 for alerting the subject upon the detection of drowsiness.
  • Processing means 140 are typically powered by a power supply 146.
  • the alerting module 144 typically activates a loudspeaker 148, such as an earphone, a hearing-aid type speaker, or a small speaker
  • alerting module 144 located near the subject, to produce an audible alerting sound.
  • the alerting module 144 produces the alerting sound at a low
  • the alerting sound is alternatively selected by the alerting module 144 from among a multiplicity of different recorded or programmed sounds such that the same, sound is never used to alert the subject twice in a row. Alternatively, the same sound may be used two or more times in a row.
  • Pre-sleep behavior tends to be characterized by quiescent behavior and the relaxation of facial muscles.
  • awake behavior is characterized at least in part by eye, facial and head movements, blinking, and or talking.
  • the bioelectric signals to be obtained from the vicinity of the eyes while a subject is awake have substantial signal amplitudes in a high frequency range of typically
  • the average amplitudes of the biosignals obtained at the onset of drowsiness are much smaller than those obtained from an awake subject.
  • the high frequency range typically characterizes muscle activity and the low frequency range typically
  • the alerting module 144 is to be activated whenever the amplitudes of the biosignals in the low and/or high frequency ranges drop substantially below baseline values, measured when the subject is awake, for more than a selectable number of seconds.
  • the baseline values may be recorded during a set-up period occurring at the beginning of the use of the apparatus 130 or they may be updated periodically during use of the apparatus 130.
  • Typical RMS amplitude curves of biosignals representing a several minute period in which a typical subject falls asleep are shown in Figs. 10A and 10B.
  • the biosignals are from electrode assemblies 10 located near the eyes.
  • the abscissas of the graphs in Figs. 10A and 10B are in minutes and the ordinates are in
  • the pass band for the low frequency signal is 0.5 - 10 Hz and the pass band for the high frequency signal is 30 - 1500 Hz.
  • curve 150 is the actual RMS amplitude of the high frequency portion of the
  • Curve 152 is a typical baseline curve calculated by averaging the RMS values of the biosignal using a moving 1 - 2 minute window ending 30 - 60 seconds before the current time.
  • threshold level 156 is 50% of the current baseline value.
  • T1 a predetermined period of time
  • amplitude levels and indicated by reference numeral 158 typically occurs after the activation point of the alerting module 144, assuming that the alerting module 144 has not been activated.
  • Fig. 10B illustrates the low frequency
  • curve 160 is the low frequency RMS amplitude curve similar to curve 150.
  • Curve 162 is a typical baseline curve calculated as described
  • the predetermined threshold level, marked 166 is typically 50% and the
  • T2 predetermined period
  • the alerting module 144 can be activated when one of the two curves 150 or 160 achieves the drowsiness condition or when both simultaneously indicate the drowsiness condition, or when one achieves the drowsiness condition and the other achieves it within a predetermined period of time.
  • alerting module 144 can be periodically activated to check that the subject is still alert. In such an embodiment, the time from the alert until the subject responds, herein denoted the response time, is measured. Alerting module 144 can also be activated in relation to the length of the response time or the length of time a subject remains active or quiescent after previously being alerted.
  • Head motions are optionally detected by head motion sensors 134a and 134b for those applications which involve substantial head motion. Their signals are processed in a manner similar to that of the low frequency range signals described hereinabove. The head motion activity is then removed from the low and high frequency biosignals by means of real-time adaptive filtering software such as that described in chapter 9, "Adaptive Filtering," of Biomedical Signal Processing: Vol. 1, written by Arnon Cohen, published by CRC Press, Boca Raton, F1. in 1986 and incorporated herein by reference.
  • Subject response to the alert is detected by means of the acquisition electronics as described hereinabove.
  • Response detection is achieved by
  • the present amplitude is compared to that recorded when the subject is known to be aware and alert.
  • the present amplitude is compared to that recorded when the subject is known to be aware and alert.
  • amplitude is compared to a peak amplitude obtained when the subject is blinking but is otherwise quiescent, or the signal is compared to a waveform of representative blinks recorded when the subject is otherwise quiescent, using matched filter or cross correlation methods such as those presented in the above reference by
  • the response detection means are activated and the response time is measured.
  • the response time is additionally compared to the previous response time. If the response time has increased, typically indicating an increase in drowsiness, the time between periodic alerting is decreased.
  • the alerting module 144 is operative to gradually increase the intensity of the audible sound until the response detection means
  • Detector module 144 comprises two preamplifiers 172, of the type described with reference to Fig. 6, for amplifying by a gain of typically 500 to 1000, differential biosignals received from two pairs of electrode assemblies 10.
  • Preamplifiers 172 are not incorporated into the
  • processing means 140 if the incoming signals are
  • Each preamplifier 172 receives signals from one pair of electrode assemblies 10.
  • the two amplified signals are sent to a pair of identical low frequency band pass filters 174 for filtering frequencies in a pass band of typically 1 - 10 Hz and to a pair of identical high frequency band pass filters 176 for filtering frequencies in a pass band of typically 100 - 1500 Hz.
  • Filters 174 and 176 attenuate frequencies outside their respective pass bands by at least 12 dB per octave.
  • Signal processors 178 typically receive the filtered high frequency signals from filters 176 and rectify, peak sense and integrate them, producing relatively smooth signals. The resultant signals are proportional to the peak-to-peak amplitude of the filtered high frequency signals and have a limited bandwidth of typically 0 - 100 Hz.
  • a typical signal processor 178 is shown in Fig. 12 where integrated circuits V 1 are the TL064 chips manufactured by Motorola and integrated circuits V 2 are the LM393 chips,
  • Amplifier pairs 180 and 182 amplify the respective, filtered low and high frequency signals received, respectively, from filters 174 and processors 178, to an amplitude in the range of a few, typically 1 - 5, volts.
  • An A/D converter 184 typically a multichannel A/D converter having one channel for each electrode assembly pair input, converts the amplified signals from amplifiers 180 and 182 to four digital signals of at least 2N i samples per second, where N i is the bandwidth of the ith channel. The resolution of the samples is typically eight bits.
  • A/D converter 184 can optionally be a combination of an A/D converter and a multiplexer.
  • a microprocessor 186 typically a low power consuming microprocessor such as the Motorola 68HC11, processes the four digital signals in accordance with the method described hereinabove with reference to Figs. 10A and 10B. At the appropriate moments, the
  • microprocessor 186 activates alerting module 144, described in more detail hereinbelow.
  • Alerting module 144 comprises an audio
  • generator 188 such as a tone or voice synthesizer, which is controlled by microprocessor 186, for producing one of a multitude of preprogrammed tone signals or sounds stored in microprocessor 186, and an audio amplifier 190, such as a Walkman audio amplifier
  • Audio amplifier 190 is also controlled by microprocessor 186 to enable the alerting module 144 to vary the amplitude of the alerting sound according to the subject's response or lack thereof.
  • the tone signals emanating from audio amplifier 190 are made audible by loudspeaker 148.
  • Figs. 14A - 14C respectively illustrate front, back and side views of an embodiment of a fetal biosignal probe 200 using any of the electrode assemblies of Fig. 1.
  • the probe 200 typically comprises a capacitive electrode assembly 202, such as described hereinabove particularly with respect to Fig. 1, and a wiring cable 204 for connecting the electrode 202 to a data
  • the electrode 202 and wiring cable 204 are typically embedded in a relatively flat probe body 206 which is typically comprised of a stiff but flexible material, such as nylon or other common plastic, and is of sufficient length to reach from a fetal scalp to completely outside the mother's cervix.
  • a typical length is between 40 - 50 cm.
  • the probe 200 additionally comprises a
  • reference electrode 208 for providing an electrical reference signal, similar to those described hereinabove in Fig. 1.
  • the reference electrode 208 is mounted on an outer surface 210 of body 206 facing the fetal scalp and its wiring 212 is embedded in body 206.
  • the wiring cables 204 and 212 may comprise a flexible printed circuits whose wires serve to provide the wiring to electrodes 202 and 208, in a manner similar to that illustrated in Fig. 5.
  • Frictionous area 214 On the outer scalp-side surface 210 of probe 200 is a frictionous or adherent area 214 for enabling the probe 200 to adhere to the scalp of the fetus, thereby preventing the probe 200 from slipping relative to the surface of the scalp.
  • Frictionous area 214 is typically comprised of a layer of ribbed, soft rubber such as that used for dishwashing gloves, such as manufactured by Playtex, Inc. of the USA.
  • a surface 216, on the opposite side of the probe from surface 210, includes a smooth surface 218, on the opposite side of the probe 200 from area 214, for enabling generally easy slippage of the probe 200 against the uterine wall.
  • the probe 200 is typically operated as
  • the probe 200 is inserted into the uterus of the mother and is positioned in a desired position on the scalp of a fetus. Area 214 and surface 218 enable the probe 200 to travel with the fetal head as it emerges during delivery.
  • Figs. 15A - 15C respectively illustrate front, back and side views of an alternative embodiment of fetal biosignal probe 200 using the electrode of Fig. 1. Similar reference numerals refer to similar elements.
  • the probe 200 is optionally used in conjunction with a cover sheath 220 which covers the entire length of probe 200 and is preferably made of a thin plastic, such as polyethylene or other common plastic.
  • Sheath 220 is preferably sterile and is preferably disposable.
  • the reference electrode 208 is mounted on an outer surface 222 of sheath 220 facing the fetal scalp.
  • the electrode wiring, here also labeled 212 passes through the wall of sheath 220 and runs down its length to where it exits the sheath 220.
  • the frictionous or adherent area, here labeled 224 is similar to that described above, and is on the outer surface 222 of sheath 220.
  • the smooth surface, here labeled 226, is on an outer surface 228 of sheath 220.
  • FIG. 200 illustrates a system for obtaining fetal biosignals during delivery using at least two probes 200 of either of the abovementioned embodiments.
  • the system typically comprises at least two probes 200 for obtaining differential fetal signals typically placed on opposite sides of the fetus's head.
  • the system also comprises signal processing equipment similar to those described hereinabove with reference to Fig. 4.
  • the signal processing equipment comprises amplifiers 230, connected to probe 200 via electrode wiring 212 and wiring cable 204, digital circuitry 240 and a power supply 245.
  • amplifiers 230 connected to probe 200 via electrode wiring 212 and wiring cable 204, digital circuitry 240 and a power supply 245.
  • an ECG amplifier 250 such as a Hewlett Packard fetal monitor model 8030 or 8040, is included in the signal processing equipment.
  • the output of amplifiers 230 and the ECG signal from amplifier 250 are typically input to digital circuitry 240 containing real-time adaptive filter software 260, such as described in Chapter 9 of the book Biomedical Signal Processing: Vol. 1 of Arnon Cohen.
  • Software 260 removes the fetal ECG signal from the differential biosignal obtained from probes 200, providing the EEG and EMG signals free of ECG artifact.
  • the ECG amplifier 250 preferably obtains the unamplified biosignals from one of probes 200 via the input connections to amplifiers 230.
  • a maternal reference electrode 270 such as the standard silver/silver-chloride gel disposable type disclosed hereinabove, typically placed on the mother's thigh.
  • ECG amplifier 250 can be incorporated into amplifiers 230.
  • a single fetal probe 200 and the maternal reference electrode 270 can be used in conjunction with ECG amplifier 250.
  • CFFT Critical Flicker Fusion Test
  • CFFT cognitive function
  • Numerous clinical studies have documented the effects of various drugs, fatigue and other factors on the CFFT. Many of them are reported in the article "Critical Flicker Frequency and Psychotropic Drugs in Normal Human Subjects - A Review", by Smith and Misiak, published in Psychopharmacology, Vol. 47, pp. 175 - 182, 1976. These studies have shown that a reduced CFFT frequency score can be indicative of impairment of cognitive functions, such as reaction time, visual perception and decision making.
  • CFFT CF-frequency frequency division multiple access filter
  • the subject is required to specify the highest oscillation frequency, known as the critical flicker fusion frequency, at which the light source appears to flicker.
  • the critical flicker fusion frequency the highest oscillation frequency
  • the critical flicker fusion frequency the lowest oscillation frequency
  • the light source is perceived by the subject to be constantly lit, denoted herein as
  • the purpose of the present invention is to provide a reliable CFFT score even for subjects who may have an interest in trying to avoid providing an
  • Such action by a subject is likely if a low or reduced CFFT frequency score indicates that the subject has an impairment.
  • the apparatus of the present invention makes it highly improbable for a subject to claim a higher CFFT
  • the non-flickering sources are otherwise identical in appearance to the flickering sources.
  • the light sources are LEDs it being understood that any light source capable of rapid intensity modulation is suitable.
  • a preferred embodiment of the apparatus comprises a set of 12 identical LEDs 300 capable of rapid intensity oscillation, arranged in a circular pattern similar to a clock face. Other patterns of multiple light sources, such as linear arrays, matrices or dot arrays can alternatively be employed.
  • Driving electronic circuitry 302, shown in detail in Fig. 18, under the control of a computer 304 supplies oscillating electric signals to the LEDs 300, thereby causing their intensities to vary accordingly.
  • the LEDs 300 are divided into two groups, a background group 308 and a flicker group 310.
  • the flicker group 310 comprises at least one LED.
  • the LEDs of the background group 308 are oscillated at a
  • Any frequency can be used to drive the LEDs of the flicker group 310.
  • the oscillations are
  • LEDs of the flicker group 310 are initially oscillated at a frequency of approximately 60 Hz, a frequency known to be above the critical flicker frequency.
  • oscillation frequency of the flicker group 310 is reduced, typically at a rate of 1 Hz per second, until the subject identifies to the computer 304 via the keyboard 306 that he detects at least one of the LEDs 300 flickering.
  • the computer 304 then stops reducing the oscillation frequency of the flicker group 310.
  • the recording of the subject's CFFT frequency score is dependent on his identifying the correct flicker group. Incorrect identification of the flicker group can be indicative of a deliberate attempt to gain a fraudulent score.
  • the subject has only a 1 in 12 chance of guessing correctly the flickering LED before his true CFFT is reached. If two LEDs are used, the subject has less than a 1% chance of correctly pinpointing which LEDs are flickering before his true CFFT is reached.
  • the proposed apparatus prevents a subject from deliberately raising his true CFFT, but the subject is also unlikely to report a CFFT below his true readout. This is because the subject, after detecting flickering of one of the LEDs, is not likely to waste time in trying to recognize the entire flicker group while the oscillation frequency continues to drop, thereby giving a CFFT score below his true score.
  • the subject is more likely to first notify the computer 304 that he has detected flickering in at least one of the LEDs. He can then identify the other flickering LEDs without lowering his score.
  • Time_Since_Alarm [time since last alarm was sounded]
  • BSR is % time in BSR array recalculate Burst Supressicn Ratio below Quiet_Threshold

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Animal Behavior & Ethology (AREA)
  • Biomedical Technology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Surgery (AREA)
  • Physics & Mathematics (AREA)
  • Molecular Biology (AREA)
  • Medical Informatics (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Pathology (AREA)
  • Biophysics (AREA)
  • Ophthalmology & Optometry (AREA)
  • Cardiology (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Hospice & Palliative Care (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Psychology (AREA)
  • Developmental Disabilities (AREA)
  • Child & Adolescent Psychology (AREA)
  • Radiology & Medical Imaging (AREA)
  • Social Psychology (AREA)
  • Pediatric Medicine (AREA)
  • Psychiatry (AREA)
  • Educational Technology (AREA)
  • Pregnancy & Childbirth (AREA)
  • Gynecology & Obstetrics (AREA)
  • Reproductive Health (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Dentistry (AREA)
  • Physiology (AREA)
  • Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)

Abstract

Appareil pour placer des électrodes (10) sur un corps humain afin d'obtenir des biosignaux humains. L'appareil comporte des éléments de revêtement proche du corps (70), une pluralité d'électrodes (10) placées sur les éléments de revêtement proche du corps (70), un élément de couverture amovible (12) servant d'interface stérile entre la peau et au moins une des électrodes, ainsi qu'un élément de liaison pour relier l'élément de couverture à au moins une des électrodes. On décrit également diverses applications de l'appareil, notamment pour détecter la somnolence chez un sujet et pour attirer son attention sur ce fait, et une sonde de biosignaux f÷taux.
PCT/US1991/001260 1990-02-28 1991-02-26 Appareil pour placer des electrodes WO1991013584A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IL93579 1990-02-28
IL93579A IL93579A0 (en) 1990-02-28 1990-02-28 Apparatus for rapidly preparing to obtain biosignals

Publications (1)

Publication Number Publication Date
WO1991013584A1 true WO1991013584A1 (fr) 1991-09-19

Family

ID=11060967

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1991/001260 WO1991013584A1 (fr) 1990-02-28 1991-02-26 Appareil pour placer des electrodes

Country Status (4)

Country Link
EP (1) EP0517793A4 (fr)
CA (1) CA2077191A1 (fr)
IL (1) IL93579A0 (fr)
WO (1) WO1991013584A1 (fr)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993020499A1 (fr) * 1992-03-31 1993-10-14 The Research Foundation Of State University Of New York Appareil et procede destines a une interface suivant les mouvements des yeux
US5311877A (en) * 1991-10-02 1994-05-17 Mazda Motor Corporation Waking degree maintaining apparatus
US5517021A (en) * 1993-01-19 1996-05-14 The Research Foundation State University Of New York Apparatus and method for eye tracking interface
US5622168A (en) * 1992-11-18 1997-04-22 John L. Essmyer Conductive hydrogels and physiological electrodes and electrode assemblies therefrom
EP0788329A1 (fr) * 1994-10-24 1997-08-13 TRANSSCAN RESEARCH & DEVELOPMENT CO. LTD. Dispositifs d'imagerie par impedance et sonde multi-element utilisee a cet effet
FR2760348A1 (fr) * 1997-03-05 1998-09-11 Aecl Equipement de stimulation oculaire et de posturographie, notamment pour le diagnostic des troubles de l'equilibre
US6055452A (en) * 1994-10-24 2000-04-25 Transcan Research & Development Co., Ltd. Tissue characterization based on impedance images and on impedance measurements
US6099124A (en) * 1999-12-14 2000-08-08 Hidaji; Faramarz Ophthalmological system and method
WO2002032305A1 (fr) * 2000-10-16 2002-04-25 Instrumentarium Corporation Methode et appareil permettant de determiner l"etat cerebral d"un patient par une reponse rapide
US6560480B1 (en) 1994-10-24 2003-05-06 Transscan Medical Ltd. Localization of anomalies in tissue and guidance of invasive tools based on impedance imaging
US6678552B2 (en) 1994-10-24 2004-01-13 Transscan Medical Ltd. Tissue characterization based on impedance images and on impedance measurements
US6801803B2 (en) 2000-10-16 2004-10-05 Instrumentarium Corp. Method and apparatus for determining the cerebral state of a patient with fast response
US7302292B2 (en) 2002-04-04 2007-11-27 Mirabel Medical Ltd. Breast cancer screening
EP2281604A1 (fr) * 2002-10-02 2011-02-09 Standen Ltd. Dispositif permettant de traiter une tumeur par un champ électrique
WO2011038767A1 (fr) * 2009-10-01 2011-04-07 Widex A/S Dispositif de surveillance portable avec aide auditive et dispositif de surveillance d'électroencéphalogramme
WO2013110846A1 (fr) * 2012-01-26 2013-08-01 Nokia Corporation Capteur capacitif de suivi oculaire
US20130274583A1 (en) * 2010-11-15 2013-10-17 Sandy L. Heck Electrodes Adapted for Transmitting or Measuring Voltages Through Hair
WO2014005974A1 (fr) * 2012-07-02 2014-01-09 Sense Innovation Limited Système de biofeedback
WO2015055156A1 (fr) * 2013-10-15 2015-04-23 Univerzita Karlova V Praze, Lekarska Fakulta V Hradci Kralove Dispositif mobile pour la surveillance à long terme des fonctions visuelles et cérébrales
DE102013021823A1 (de) * 2013-12-21 2015-06-25 Valeo Schalter Und Sensoren Gmbh Vorrichtung zum Erfassen einer elektrodermalen Aktivität einer Person, Lenkrad, Kraftfahrzeug und entsprechendes Verfahren
WO2016195932A1 (fr) * 2015-06-03 2016-12-08 Microsoft Technology Licensing, Llc Capteurs capacitifs pour déterminer la direction du regard
WO2017025553A1 (fr) * 2015-08-11 2017-02-16 Bioserenity Procede de mesure d'un parametre electrophysiologique au moyen d'un capteur electrode capacitive de capacite controlee
DE102017117053A1 (de) 2017-04-24 2018-10-25 Zeisberg GmbH Gesichtsauflage
US20220350137A1 (en) * 2021-04-23 2022-11-03 University Of Washington Capacitance-based eye tracker
WO2024005887A1 (fr) * 2022-06-28 2024-01-04 Microsoft Technology Licensing, Llc Détermination de charge sur un capteur de suivi facial

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111617382B (zh) * 2020-05-20 2023-08-25 四川大学华西医院 一种预防压力性损伤的电刺激装置

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3744482A (en) * 1971-06-29 1973-07-10 Hittman Ass Inc Dry contact electrode with amplifier for physiological signals
DE2633439A1 (de) * 1976-07-24 1978-01-26 Martin Dipl Ing Schuler Mit einem verstaerker versehene isolierte elektrode zur ableitung von biosignalen
US4078553A (en) * 1976-06-14 1978-03-14 Jean Duroux Methods for investigating internal physiological phenomena
US4425921A (en) * 1981-01-19 1984-01-17 Senoh Kabushiki Kaisha Apparatus for checking pulse and heart rates
US4697598A (en) * 1985-04-25 1987-10-06 Westinghouse Electric Corp. Evoked potential autorefractometry system
US4763660A (en) * 1985-12-10 1988-08-16 Cherne Industries, Inc. Flexible and disposable electrode belt device
WO1989005672A1 (fr) * 1987-12-14 1989-06-29 Intrinsic Ag Procede pour influer sur l'environnement electrique immediat d'un etre vivant

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1442296A (en) * 1972-08-16 1976-07-14 Secr Defence Electrodes

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3744482A (en) * 1971-06-29 1973-07-10 Hittman Ass Inc Dry contact electrode with amplifier for physiological signals
US4078553A (en) * 1976-06-14 1978-03-14 Jean Duroux Methods for investigating internal physiological phenomena
DE2633439A1 (de) * 1976-07-24 1978-01-26 Martin Dipl Ing Schuler Mit einem verstaerker versehene isolierte elektrode zur ableitung von biosignalen
US4425921A (en) * 1981-01-19 1984-01-17 Senoh Kabushiki Kaisha Apparatus for checking pulse and heart rates
US4697598A (en) * 1985-04-25 1987-10-06 Westinghouse Electric Corp. Evoked potential autorefractometry system
US4763660A (en) * 1985-12-10 1988-08-16 Cherne Industries, Inc. Flexible and disposable electrode belt device
WO1989005672A1 (fr) * 1987-12-14 1989-06-29 Intrinsic Ag Procede pour influer sur l'environnement electrique immediat d'un etre vivant

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP0517793A4 *

Cited By (51)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5311877A (en) * 1991-10-02 1994-05-17 Mazda Motor Corporation Waking degree maintaining apparatus
US5360971A (en) * 1992-03-31 1994-11-01 The Research Foundation State University Of New York Apparatus and method for eye tracking interface
WO1993020499A1 (fr) * 1992-03-31 1993-10-14 The Research Foundation Of State University Of New York Appareil et procede destines a une interface suivant les mouvements des yeux
US5622168A (en) * 1992-11-18 1997-04-22 John L. Essmyer Conductive hydrogels and physiological electrodes and electrode assemblies therefrom
US5517021A (en) * 1993-01-19 1996-05-14 The Research Foundation State University Of New York Apparatus and method for eye tracking interface
EP0788329A1 (fr) * 1994-10-24 1997-08-13 TRANSSCAN RESEARCH & DEVELOPMENT CO. LTD. Dispositifs d'imagerie par impedance et sonde multi-element utilisee a cet effet
US6560480B1 (en) 1994-10-24 2003-05-06 Transscan Medical Ltd. Localization of anomalies in tissue and guidance of invasive tools based on impedance imaging
EP0788329A4 (fr) * 1994-10-24 1999-11-10 Transscan Res & Dev Co Ltd Dispositifs d'imagerie par impedance et sonde multi-element utilisee a cet effet
US6055452A (en) * 1994-10-24 2000-04-25 Transcan Research & Development Co., Ltd. Tissue characterization based on impedance images and on impedance measurements
US7141019B2 (en) 1994-10-24 2006-11-28 Mirabel Medical Systems Ltd. Tissue characterization based on impedance images and on impedance measurements
US6308097B1 (en) 1994-10-24 2001-10-23 Transscan Medical Ltd. Tissue characterization based on impedance images and on impedance measurements
US6678552B2 (en) 1994-10-24 2004-01-13 Transscan Medical Ltd. Tissue characterization based on impedance images and on impedance measurements
US6421559B1 (en) 1994-10-24 2002-07-16 Transscan Medical Ltd. Tissue characterization based on impedance images and on impedance measurements
FR2760348A1 (fr) * 1997-03-05 1998-09-11 Aecl Equipement de stimulation oculaire et de posturographie, notamment pour le diagnostic des troubles de l'equilibre
US6099124A (en) * 1999-12-14 2000-08-08 Hidaji; Faramarz Ophthalmological system and method
WO2002032305A1 (fr) * 2000-10-16 2002-04-25 Instrumentarium Corporation Methode et appareil permettant de determiner l"etat cerebral d"un patient par une reponse rapide
US6731975B1 (en) 2000-10-16 2004-05-04 Instrumentarium Corp. Method and apparatus for determining the cerebral state of a patient with fast response
US6801803B2 (en) 2000-10-16 2004-10-05 Instrumentarium Corp. Method and apparatus for determining the cerebral state of a patient with fast response
US7228169B2 (en) 2000-10-16 2007-06-05 Ge Healthcare Finland Oy Method and apparatus for determining the cerebral state of a patient with fast response
US8391968B2 (en) 2001-04-04 2013-03-05 Mirabel Medical Systems Ltd. Breast classification based on impedance measurements
US7302292B2 (en) 2002-04-04 2007-11-27 Mirabel Medical Ltd. Breast cancer screening
EP2281604A1 (fr) * 2002-10-02 2011-02-09 Standen Ltd. Dispositif permettant de traiter une tumeur par un champ électrique
WO2011038767A1 (fr) * 2009-10-01 2011-04-07 Widex A/S Dispositif de surveillance portable avec aide auditive et dispositif de surveillance d'électroencéphalogramme
US9782103B2 (en) 2009-10-01 2017-10-10 Widex A/S Portable monitoring device with hearing aid and EEG monitor
KR101335740B1 (ko) 2009-10-01 2013-12-02 비덱스 에이/에스 Eeg 모니터링을 위한 방법 및 시스템, 및 보청기와 eeg 모니터를 갖는 휴대용 모니터링 디바이스
US20130274583A1 (en) * 2010-11-15 2013-10-17 Sandy L. Heck Electrodes Adapted for Transmitting or Measuring Voltages Through Hair
WO2013110846A1 (fr) * 2012-01-26 2013-08-01 Nokia Corporation Capteur capacitif de suivi oculaire
CN104066371A (zh) * 2012-01-26 2014-09-24 诺基亚公司 电容性眼球追踪传感器
US9414746B2 (en) 2012-01-26 2016-08-16 Nokia Technologies Oy Eye tracking
GB2518113A (en) * 2012-07-02 2015-03-11 Sense Innovation Ltd Biofeedback system
US11517257B2 (en) 2012-07-02 2022-12-06 Emteq Limited Biofeedback system
US10398373B2 (en) 2012-07-02 2019-09-03 Emteq Limited Biofeedback system
GB2518113B (en) * 2012-07-02 2018-04-11 Emteq Ltd Biofeedback system
WO2014005974A1 (fr) * 2012-07-02 2014-01-09 Sense Innovation Limited Système de biofeedback
WO2015055156A1 (fr) * 2013-10-15 2015-04-23 Univerzita Karlova V Praze, Lekarska Fakulta V Hradci Kralove Dispositif mobile pour la surveillance à long terme des fonctions visuelles et cérébrales
DE102013021823A1 (de) * 2013-12-21 2015-06-25 Valeo Schalter Und Sensoren Gmbh Vorrichtung zum Erfassen einer elektrodermalen Aktivität einer Person, Lenkrad, Kraftfahrzeug und entsprechendes Verfahren
CN107743605A (zh) * 2015-06-03 2018-02-27 微软技术许可有限责任公司 用于确定眼睛注视方向的电容传感器
US20160353988A1 (en) * 2015-06-03 2016-12-08 Microsoft Technology Licensing, Llc Capacitive sensors for determining eye gaze direction
WO2016195932A1 (fr) * 2015-06-03 2016-12-08 Microsoft Technology Licensing, Llc Capteurs capacitifs pour déterminer la direction du regard
US11287930B2 (en) 2015-06-03 2022-03-29 Microsoft Technology Licensing, Llc Capacitive sensors for determining eye gaze direction
US9888843B2 (en) * 2015-06-03 2018-02-13 Microsoft Technology Licensing, Llc Capacitive sensors for determining eye gaze direction
CN107743605B (zh) * 2015-06-03 2021-01-26 微软技术许可有限责任公司 用于确定眼睛注视方向的电容传感器
CN108289609A (zh) * 2015-08-11 2018-07-17 比奥塞雷妮蒂公司 用于借助于受控电容的电容式电极传感器测量电生理参数的方法
WO2017025553A1 (fr) * 2015-08-11 2017-02-16 Bioserenity Procede de mesure d'un parametre electrophysiologique au moyen d'un capteur electrode capacitive de capacite controlee
FR3039979A1 (fr) * 2015-08-11 2017-02-17 Bioserenity Procede de mesure d'un parametre electrophysiologique au moyen d'un capteur electrode capacitive de capacite controlee
DE102017117053A1 (de) 2017-04-24 2018-10-25 Zeisberg GmbH Gesichtsauflage
DE102017117053B4 (de) * 2017-04-24 2021-03-11 Zeisberg GmbH Gesichtsauflage
US20220350137A1 (en) * 2021-04-23 2022-11-03 University Of Washington Capacitance-based eye tracker
US11698527B2 (en) * 2021-04-23 2023-07-11 University Of Washington Capacitance-based eye tracker
US20230333372A1 (en) * 2021-04-23 2023-10-19 University Of Washington Capacitance-based eye tracker
WO2024005887A1 (fr) * 2022-06-28 2024-01-04 Microsoft Technology Licensing, Llc Détermination de charge sur un capteur de suivi facial

Also Published As

Publication number Publication date
IL93579A0 (en) 1990-11-29
EP0517793A1 (fr) 1992-12-16
EP0517793A4 (en) 1993-03-17
CA2077191A1 (fr) 1991-08-29

Similar Documents

Publication Publication Date Title
WO1991013584A1 (fr) Appareil pour placer des electrodes
WO1993002616A1 (fr) Appareil servant a mettre en place des electrodes
US20220192513A1 (en) Remote Physiological Monitor
US10835179B2 (en) Headset for bio-signals acquisition
Looney et al. The in-the-ear recording concept: User-centered and wearable brain monitoring
US8700142B2 (en) Brain function scan system
ES2776178T3 (es) Sistemas para detectar bio-señales basadas en el cerebro
US6052619A (en) Brain function scan system
US20070112277A1 (en) Apparatus and method for the measurement and monitoring of bioelectric signal patterns
US20100185115A1 (en) Apparatus for evoking and recording bio-potentials
US20180333066A1 (en) Apparatus for measuring electroencephalogram, system and method for diagnosing and preventing dementia
US20050020934A1 (en) Physiological monitoring
KR100945678B1 (ko) 헬멧을 이용한 다중생체신호 측정장치
CA3007675C (fr) Casque pour acquisition de bio-signaux
WO2010079257A1 (fr) Dispositif, appareil et procédé de mesure d'informations biologiques
CN110772225A (zh) 一种人体生理信号采集设备及方法
WO2017060560A1 (fr) Agencement pour conduire des mesures d'électrode
von Rosenberg et al. Smart helmet: monitoring brain, cardiac and respiratory activity
CN211985399U (zh) 一种人体生理信号采集设备
US20240206794A1 (en) In-ear electroencephalography electrodes with multi-parameter vitals monitor connectivity
US20230263409A1 (en) Monitoring device for monitoring of vital signs
US20220409117A1 (en) Method and apparatus for detecting changes in blood flow in the head of a subject
WO2024090527A1 (fr) Dispositif de mesure de biosignal
WO2024224433A1 (fr) Dispositif et procédé de surveillance et de modulation de l'excitabilité cérébrale
KR20220124410A (ko) 뉴로피드백을 기반으로 하는 원격제어 및 자동화 두뇌훈련 시스템

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU NL SE

WR Later publication of a revised version of an international search report
WWE Wipo information: entry into national phase

Ref document number: 1991905580

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2077191

Country of ref document: CA

WWP Wipo information: published in national office

Ref document number: 1991905580

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1991905580

Country of ref document: EP