Neural systems of visual attention responding to emotional gestures

Abstract

Humans are the only species known to use symbolic gestures for communication. This affords a unique medium for nonverbal emotional communication with a distinct theoretical status compared to facial expressions and other biologically evolved nonverbal emotion signals. While a frown is a frown all around the world, the relation of emotional gestures to their referents is arbitrary and varies from culture to culture. The present studies examined whether such culturally based emotion displays guide visual attention processes. In two experiments, participants passively viewed symbolic hand gestures with positive, negative and neutral emotional meaning. In Experiment 1, functional magnetic resonance imaging (fMRI) measurements showed that gestures of insult and approval enhance activity in selected bilateral visualassociative brain regions devoted to object perception. In Experiment 2, dense sensor event-related brain potential recordings (ERP) revealed that emotional hand gestures are differentially processed already 150 ms poststimulus. Thus, the present studies provide converging neuroscientific evidence that emotional gestures provoke the cardinal signatures of selective visual attention regarding brain structures and temporal dynamics previously shown for emotional face and body expressions. It is concluded that emotionally charged gestures are efficient in shaping selective attention processes already at the level of stimulus perception.