Wavelet entropy in event-related potentials: a new method shows ordering of EEG oscillations.
In this work we show the application of a measure of entropy defined from the wavelet transform, namely the wavelet entropy (WS), to the study of event-related potentials (ERPs). WS was computed for ERPs recorded from nine healthy subjects with three different types of stimuli, among them target stimuli in a cognitive task. A significant decrease of entropy was correlated with the responses to target stimuli (P300), thus showing that these responses correspond to a more "ordered" state than the spontaneous EEG. Furthermore, we propose the WS as a quantitative measure for such transitions between EEG ("disordered state") and ERP ("ordered state").
Quiroga
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RQ
Institute of Physiology, Medical University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany.
Rosso
O A
OA
Başar
E
E
Schürmann
M
M
D000328:Adult; D004569:Electroencephalography; D019277:Entropy; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008959:Models, Neurological; D010507:Periodicity