Response and habituation of the amygdala during processing of emotional prosody.

The role of the amygdala in processing acoustic information of affective value is still under debate. Using event-related functional MRI (fMRI), we showed increased amygdalar responses to various emotions (anger, fear, happiness, eroticism) expressed by prosody, a means of communication bound to language and consequently unique to humans. The smallest signal increases were found for fearful prosody, a finding that could not be explained by rapid response habituation to stimuli of this emotional category, challenging classical theories about fear specificity of the human amygdala. Our results converge with earlier neuroimaging evidence investigating emotional vocalizations, and these neurobiological similarities suggest that the two forms of communication might have common evolutionary roots.