A frequency synchronization study on the temporal and spatial evolution of emotional visual processing using wavelet entropy and IAPS picture collection

Abstract

Traditional analysis of emotional neurophysiological data was mainly performed either by detecting temporal changes in the event-related potentials or by simple frequency analysis. Here, the notion of the time-evolving wavelet entropy is used for providing a measurement of the frequency synchronization during passive viewing of emotion evocative pictures selected from the International Affective Picture System (IAPS). The aim of this work is to study the temporal and spatial evolution of the dynamical frequency changes modulating the event-related potentials evoked by pleasant and unpleasant visual stimuli of varying arousal. The results obtained from the method's application to short EEG data, indicate that both the emotional dimensions and gender modulate the frequency synchronization patterns. Therefore, their study over short temporal windows may enhance the knowledge extracted from the classical methods used. © 2010 International Federation for Medical and Biological Engineering.