WAVELET TRANSFORMS AND SURROGATE DATA FOR ELECTROENCEPHALOGRAPHIC SPIKE AND SEIZURE LOCALIZATION

Wavelet transforms are used to analyze electroencephalographic data re corded from individual subdural electrodes and 2-D electrode grids in direct contact with the brain. Surrogate data techniques are used to f ilter noise and resolve structure in the data. Spike and seizure detec tion from individual electrodes with wavelet transforms are compared w ith windowed Fourier transforms. Wavelet transforms are a powerful mea ns to identify epileptiform activity such as spikes from such data and also offer a method to localize the foci of epileptic seizures from e lectrode grids.