The temporal dynamics of processing emotions from vocal, facial, and bodily expressions

Face-to-face communication works multimodally. Not only do we employ vocal and facial expressions; body language provides valuable information as well. Here we focused on multimodal perception of emotion expressions, monitoring the temporal unfolding of the interaction of different modalities in the electroencephalogram (EEG). In the auditory condition, participants listened to emotional interjections such as "ah", while they saw mute video clips containing emotional body language in the visual condition. In the audiovisual condition participants saw video clips with matching interjections. In all three conditions, the emotions "anger" and "fear", as well as non-emotional stimuli were used. The N100 amplitude was strongly reduced in the audiovisual compared to the auditory condition, suggesting a significant impact of visual information on early auditory processing. Furthermore, anger and fear expressions were distinct in the auditory but not the audiovisual condition. Complementing these event-related potential (ERP) findings, we report strong similarities in the alpha- and beta-band in the visual and the audiovisual conditions, suggesting a strong visual processing component in the perception of audiovisual stimuli. Overall, our results show an early interaction of modalities in emotional face-to-face communication using complex and highly natural stimuli.