This application relates to physiological monitoring typically for health and fitness purposes. Specifically, this application targets health and fitness monitors that require low noise acquisition of low amplitude biopotential signals. The method herein allows measurement and acquisition of biopotential signals that are normally too small to resolve due to the noise floor limitations of modern low noise amplifiers. Examples of applications that this method enables include monitoring devices located in far proximity from the location in which a biopotential signal originates, such as a wrist worn cardiac monitor, or a device that needs to sense low amplitude, fine muscle or nerve activity in a localized region.

A textile-based hydrogel electrode comprises a textile-based backing layer, a conductive structure coupled to the textile-based backing layer, and a hydrogel body in contact with at least a first portion of the conductive structure, wherein the first portion of the conductive structure and the hydrogel body form an ionic interface configured to generate an electrical signal through the conductive structure corresponding to a biopotential change proximate to the textile-based hydrogel electrode.

According to an aspect, there is provided an apparatus (10) to control a sleep assistance device (30) for alleviating a user's pain during sleep. The apparatus (10) comprises: a receiver (11) configured to receive sensor data (14) associated with the user; a processor (12) configured to analyze the sensor data (14) to predict a pain measure of the user, and to generate a control signal (15) for the sleep assistance device (30) in accordance with the predicted pain measure; and a transmitter (13) configured to transmit the control signal (15) to the sleep assistance device (30) for alleviating pain.

A system for determining intestinal potential difference. The system includes a measurement probe including a measurement tube having a measurement lumen which houses a measurement electrode therein, a measurement fluid delivery system in fluid communication with the measurement lumen, the measurement fluid delivery system being configured to deliver an electrically-conductive fluid into the measurement lumen such that the electrically-conductive fluid is electrically coupled to the measurement electrode, and the measurement lumen including an outlet at a distal end thereof through which the electrically-conductive fluid exits the measurement lumen and contacts an intestinal tissue of a subject to provide electrical coupling between the measurement electrode and the intestinal tissue; a controller coupled to the measurement electrode configured to measure a potential difference between tire measurement electrode and a reference electrode electrically coupled to the subject.

An apparatus for measuring intracranial dynamics comprises the at least one sensing device (100): an electroencephalo-graphic electrode arrangement, which senses direct-current electroencephalographic signals from the brain, an optic measurement Marrangement (120), which directs optic radiation toward the brain through the cranium, and receives the optic radiation reflected and/or scattered therefrom, and/or a capacitive sensor arrangement (130), which senses electric potential signals of the head. The apparatus additionally comprises a data processing arrangement (150), which receives electric signals from the at least one sensing device (100), and determine data on at least one of the following dynamics: glymphatic activity, water within the cranium, brain tissue movements, water and/or electrolyte movements and intracranial pressure based on said electric signals from the at least one sensing device (100). The data processing arrangement (150) then outputs at least one piece of the data on the dynamics through a user interface (152).

A measuring apparatus is configured to be connected to an electrode to measure biopotential. The measuring apparatus has an input box to which the electrode is connected. The input box has a tubular elastic member configured to hold a cap to be mounted on the electrode, and an insertion portion configured such that the elastic member is insertable into the insertion portion. The elastic member has an entrance having a first inner diameter and a contracted portion having a second inner diameter smaller than the first inner diameter.

A signal detection device includes a measurer, an arithmetic operation unit, and signal period detector, and detects information such as a cardiac cycle with high accuracy by causing resonance of only a signal such as a heartbeat, the signal having strong pulse characteristics. The measurer measures a signal. The arithmetic operation unit performs nonlinear arithmetic operation processing for amplifying a pulse-like component of the signal measured by the measurer and suppressing a component other than the pulse-like component of the signal measured by the measurer. The signal period detector detects a periodic signal from an output of the arithmetic operation unit.

Apparatus, including a set of N electrodes (22), configured to be located in proximity to an epidermis (24) of a subject, and to acquire signals generated by electric sources within the subject. The apparatus also includes a set of M channels, configured to transfer the signals, where M is less than N, and a switch (40), configured to select, repetitively and randomly, M signals from the N electrodes and to direct the M signals to the M channels. The apparatus further includes a processor (28), configured to activate the switch, and to receive and analyze the M signals from the M channels so as to determine respective positions of the electric sources within the subject.

Systems and methods are provided herein for monitoring electrocardiogram (ECG) electrodes. Each ECG electrode is electrically connected to a patient body and a corresponding current source. A reference ECG electrode of the monitored ECG electrodes is selected. Current is injected into each electrode. Each current has a respective predetermined level. Based on the injected currents, ECG electrode voltages are generated. The injected currents are adjusted after measuring the ECG electrode voltages while the predetermined level through the reference ECG electrode is maintained. An impedance associated with each non-reference ECG electrode is determined based on the ECG electrode voltage and the injected current.

The present invention provides an electrochemical sensor that employs multiple electrode areas that are exposed for contact with a body fluid, e.g., when the sensor is inserted subcutaneously into a patient's skin. The exposed electrode areas are arranged symmetrically, such that a symmetrical potential distribution is produced when an AC signal is applied to the sensor. The sensors in accordance with these teachings can advantageously be used with AC signals to determine characteristics of the sensor and thus improve sensor performance. These teachings also provide a biocompatible sensor with multiple reference electrode areas that are exposed for contact with body fluid.