EURASIP Journal on Advances in Signal Processing 
Volume 2007 (2007), Article ID 82912, 10 pages
doi:10.1155/2007/82912
Research Article

Separation and Localisation of P300 Sources and Their Subcomponents Using Constrained Blind Source Separation

Loukianos Spyrou,1 Min Jing,1 Saeid Sanei,1 and Alex Sumich2

 1The Centre of Digital Signal Processing, School of Engineering, Cardiff University, Queen's Buildings, P.O. Box 925, Newport Road, Wales, Cardiff CF24 3AA, UK
2The Brain Image Analysis Unit, Institute of Psychiatry, King's College Hospital, London SE5 8AF, UK
Received 1 October 2005; Revised 31 May 2006; Accepted 11 June 2006

Recommended by Frank Ehlers

Abstract

Separation and localisation of P300 sources and their constituent subcomponents for both visual and audio stimulations is investigated in this paper. An effective constrained blind source separation (CBSS) algorithm is developed for this purpose. The algorithm is an extension of the Infomax BSS system for which a measure of distance between a carefully measured P300 and the estimated sources is used as a constraint. During separation, the proposed CBSS method attempts to extract the corresponding P300 signals. The locations of the corresponding sources are then estimated with some indeterminancy in the results. It can be seen that the locations of the sources change for a schizophrenic patient. The experimental results verify the statistical significance of the method and its potential application in the diagnosis and monitoring of schizophrenia.