Device and method for sensing electrical activity in tissue
First Claim
Patent Images
1. A method comprising:
- detecting electrical activity from a tissue of a user via a sensor of a headpiece worn by the user, the sensor including;
a sensor electrode to contact a first point on skin of the user;
a reference electrode to contact a second point on the skin of the user, the contact between the reference electrode and the skin of the user to cause a contact resistance between a surface of the reference electrode and the skin of the user; and
an electronics module positioned proximate the reference electrode to reduce noise, a local reference potential in the electronics module and a potential of the second point on the skin being approximately equal to allow the surface of the reference electrode to be in direct contact with the skin of the user at the second point without having to prepare the skin or use a material that decreases the contact resistance, the electrical activity represented by a voltage signal including a signal of interest, undesired signals, and noise, the electronics module including;
an amplifier to (1) amplify the signal of interest and the undesired signals within a first frequency range while (2) filtering the noise occurring in a second frequency range, which includes frequencies higher than the first frequency range, prior to transmitting the amplified signal of interest and undesired signals to one or more filters; and
transforming, with a processor and a Fourier transform, the signal of interest to form an output signal.
12 Assignments
0 Petitions
Accused Products
Abstract
An exemplary embodiment providing one or more improvements includes apparatus and methods for sensing electrical activity in tissue of a person in a manner which is substantially limits or eliminates interference from noise in a surrounding environment.
-
Citations
41 Claims
-
1. A method comprising:
-
detecting electrical activity from a tissue of a user via a sensor of a headpiece worn by the user, the sensor including; a sensor electrode to contact a first point on skin of the user; a reference electrode to contact a second point on the skin of the user, the contact between the reference electrode and the skin of the user to cause a contact resistance between a surface of the reference electrode and the skin of the user; and an electronics module positioned proximate the reference electrode to reduce noise, a local reference potential in the electronics module and a potential of the second point on the skin being approximately equal to allow the surface of the reference electrode to be in direct contact with the skin of the user at the second point without having to prepare the skin or use a material that decreases the contact resistance, the electrical activity represented by a voltage signal including a signal of interest, undesired signals, and noise, the electronics module including; an amplifier to (1) amplify the signal of interest and the undesired signals within a first frequency range while (2) filtering the noise occurring in a second frequency range, which includes frequencies higher than the first frequency range, prior to transmitting the amplified signal of interest and undesired signals to one or more filters; and transforming, with a processor and a Fourier transform, the signal of interest to form an output signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41)
-
-
31. A method comprising:
-
detecting electrical activity from a tissue of a user via a sensor of a headpiece worn by the user, the sensor including an electronics module, a sensor electrode and a reference electrode, the sensor electrode is to contact a first point on skin of the user and the reference electrode is to contact a second point on the skin of the user, the contact between the reference electrode and the skin of the user to cause a contact resistance between a surface of the reference electrode and the skin of the user, the electronics module being positioned proximate the reference electrode to reduce noise, a local reference potential in the electronics module and a potential of the second point on the skin being approximately equal to allow the surface of the reference electrode to be in direct contact with the skin of the user at the second point without having to prepare the skin or use a material that decreases the contact resistance, the electrical activity represented by a voltage signal including a signal of interest and undesired signals; transforming, with a processor, the voltage signal using a Fourier Transform to determine an energy spectrum signal based on an energy spectrum of the voltage signal; dividing the energy spectrum signal into groups of samples and separating the energy spectrum into bins that represent energy in a certain range of frequencies; summing energy in bins that have about 4-8 Hz to create a Theta band energy signal; summing energy in bins that have about 8-12 Hz to create an Alpha band energy signal; and generating the signal of interest by determining a ratio of the Alpha and Theta band energy signals, wherein the ratio includes (Theta signal−
Alpha signal)/(Theta signal+Alpha signal).
-
Specification