Optimal selection of independent components for event-related brain electrical potential enhancement

A method based on independent component analysis (ICA) is proposed for the enhancement of multi-channel event-related evoked potential (EP). P300-related independent components are selected according to the a priori knowledge of P300 spatio-temporal pattern, and clear P300 peak is reconstructed by back projection of ICA. It is used for P300 detection in P3 speller brain computer interface and for P100 detection in clinical applications. Encouraging performance is obtained by the method. The number of trials needed is reduced, but the estimated EP signal is clearer than that obtained by conventional ensemble averaging. Applied to the dataset IIb of BCI Competition 2003, the algorithm achieved an accuracy of 100% in P300 detection within 5 repetitions.