DYNAMIC EXTRACTION OF VISUAL-EVOKED POTENTIALS THROUGH SPATIAL-ANALYSIS AND DIPOLE LOCALIZATION

The dynamic extraction of evoked potential is a problem of great inter est in EEG signal processing. In this paper, a comprehensive method is presented which integrates spatial analysis and dipole localization t o make full use of the spatial-temporal information contained in the m ultichannel stimulation records. A realistic double boundary head mode l is constructed through CT scans and a two-step method devised to ove rcome the hi-posed nature of the forward problem of EEG caused by the low conductivity of the skull. As a result, visual evoked potentials c an be effectively extracted from only two consecutive records and the dynamic information of visual evoked potential thus procured. The effi ciency of the presented method has been verified by means of computer simulation and a clinical experiment.