Single Trial Evoked Potentials Study during an Emotional Processing Based on Wavelet Transform

The present study aimed at examining the event-related potentials (ERPs) single-trial extraction during an emotional processing by wavelet transform and analyzing the brain responses to emotional stimuli. ERPs were recorded from 64 electrodes in 10 healthy university students while three types of emotional pictures (pleasant, neural, and unpleasant) from the international affective picture system were presented. All the subjects showed significantly greater P300 and slow waves amplitudes at antero-inferior, medial-inferior and posterior electrode sites for pleasant and unpleasant pictures than for neural pictures and unpleasant pictures elicited more positive P300 and slow wave effects than pleasant pictures. The results indicated the effectiveness of the wavelet transform-based approach in ERP single-trial extraction and further supported the view that emotional stimuli are processed more intensely.