Pj. Durka et al., Time-frequency microstructure of event-related electro-encephalogram desynchronisation and synchronisation, MED BIO E C, 39(3), 2001, pp. 315-321
A new method is presented for the analysis of event-related EEG phenomena,
in particular event related desynchronisation (ERD) and event related synch
ronisation (ERS) related to a voluntary movement; the method offers: high t
ime-frequency resolution and, hence, increased ERD/ERS sensitivity (especia
lly in the gamma band, where improvement can exceed an order of magnitude);
the ability to analyse the whole picture of energy changes at once, withou
t setting a priori the analysed frequency bands; and a parametric descripti
on of the signal's structures. The main idea is based upon averaging energy
distributions of single EEG trials in the time-frequency plane. As the est
imator for the signal's energy density, matching pursuit is chosen, with st
ochastic Gabor dictionaries. Other possible estimates are presented on a si
mulated signal and discussed briefly. The consistency of the results with p
revious findings is evaluated on the data from a classical voluntary finger
movement experiment.