EEG analysis system
AssigneeCortical Dynamics Limited
InventorDavid Tibor Julian Liley
Life of this patent
Estimating the term…
Abstract
A process for analysing an electroencephalogram signal representative of activity of a brain, including: i) generating coefficient data for a signal representation of a portion of said signal; ii) generating first gain data representing an average amplitude of an output signal generated based on said signal representation and said coefficient data; iii) generating second gain data representing an average amplitude of said portion; and iv) generating, based on said first gain data and said second gain data, brain state data representing subcortical activity of said brain.
Claims16
A method for displaying the activity of a brain, the method including the steps of:
- (i) obtaining an electroencephalogram (EEG) signal from the brain;
- (ii) segmenting said EEG signal with a processor into either contiguous or overlapping segments comprised of a sequential number of samples of said EEG signal;
- (iii) representing said EEG segments as a fixed order autoregressive moving average (ARMA) signal representation with an autoregressive order between 8 and 13 and a moving average order between 5 and 11;
- (iv) generating AR coefficient data and MA coefficient data for said segments of said EEG signal for said fixed order ARMA signal representation;
- (v) generating signal representations for said segments of EEG signal by substituting generated AR coefficient data and MA coefficient data for said segments of EEG signal into said fixed order ARMA representation, and providing as a driving input to said EEG signal representation a zero mean unit variance Gaussian random process;
- (vi) generating an ARMA gain value as the root mean square of the amplitude values for said signal representations for said segments of EEG;
- (vii) generating brain product data representative of input to cortex by dividing the root mean square of the amplitude of the EEG signal for said segments by the ARMA gain value for said signal representations of said EEG segments;
- (viii) displaying said brain product data on display means.
A system for displaying activity of a brain, the system including a plurality of electrodes for picking up EEG signals from the brain of a subject;
- digitizing means for converting the EEG signals to a digitised EEG data signal;
- and computing means for:
- (i) segmenting said EEG signal into either contiguous or overlapping segments comprised of a sequential number of samples of said EEG signal;
- (ii) representing said EEG segments as a fixed order autoregressive moving average (ARMA) signal representation with an autoregressive order between 8 and 13 and a moving average order between 5 and 11;
- (iii) generating AR coefficient data and MA coefficient data for said segments of said EEG signal for said fixed order ARMA signal representation;
- (iv) generating signal representations for said segments of EEG signal by substituting generated AR coefficient data and MA coefficient data for said segments of EEG signal into said fixed order ARMA representation, and providing as a driving input to said EEG signal representation with a zero mean unit variance Gaussian random process;
- (v) generating an ARMA gain value as the root mean square of the amplitude values for said signal representations for said segments of EEG;
- (vi) generating brain product data representative of input to cortex by dividing the root mean square of the amplitude of the EEG signal for said segments by the ARMA gain value for said signal representations of said EEG segments;
- (vii) displaying said brain product data on display means.
Dependencies are inferred from the claim text.