Alpha Activity during Emotional Experience Revealed by ERSP

Abstract

The objective of this study is to investigate the power spectrum distribution of EEG from different emotion responses, especially in the alpha band (8~13 Hz). An affective picture stimulation task was designed to find out neuro-physiological characteristics of brain waves. Taskrelated EEG dynamics in power changes were analyzed by independent component analysis (ICA) and time-frequency. ERSP image results revealed EEG activities in the different emotion responses. Thirty healthy college students volunteered the stimulus experiment with the standard IAPS affective pictures. These affective pictures are classified in five emotion states. They are calm, happy, neutral, sad, and scared. The results show that, there were the differences of stimuli response between the left and right area in the frontal lobes. And there was stronger response of alpha band in the happy and scared states than that in the calm and sad states from the frontal lobe. However, through the central gyri area, stretching the parietal and occipital lobes, suppression of emotion appeared in the sad and scared states. Additionally, based on valence-arousal model, the ERSP maps indicate the stronger responses occur in the low alpha band (8~10 Hz) are indicated in the calm, happy, sad and scared states, while the neutral have the stronger response in the high alpha band (10~13 Hz). In the whole brain region, there were the stronger responses of alpha band in the happy state. The stronger response mostly occurs around the time range of 300 ms and 700 ms.