Estimation of the Time Delay of Epileptic Spikes by ICA
The contribution concentrates on application of Independent Compo nent Analysis (ICA) for the detection of small time delays of epileptic spikes in electroencephalographic (EEG) recordings. The ICA method isolates spike’s activity by decomposing the input EEG record into independent components. Some of them contain epileptic spikes. ICA detects the time delay of epileptic spikes between channels by separating the epileptic spikes into two or more components. We propose a method of epileptic focus location by ICA from EEG recordings which contain epileptic spikes. The analysis allows presenta tion of the results in the form of topographic maps. The method was tested on real EEG background signal with artificially simulated epileptic spikes and on EEG records containing real epileptic activity, obtained in four epileptic pa- tients. The tests were used for a comparison with the results of a visual analysis. The tests confirmed a satisfactory agreement between computerized and visual assessments.
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