Rapid Detection of Emotion from Human Vocalizations

Abstract

The rapid detection of affective signals from conspecifics is crucial for the survival of humans and other animals; if those around you are scared, there is reason for you to be alert and to prepare for impending danger. Previous research has shown that the human brain detects emotional faces within 150 msec of exposure, indicating a rapid differentiation of visual social signals based on emotional content. Here we use event-related brain potential (ERP) measures to show for the first time that this mechanism extends to the auditory domain, using human nonverbal vocalizations, such as screams. An early fronto-central positivity to fearful vocalizations compared with spectrally rotated and thus acoustically matched versions of the same sounds started 150 msec after stimulus onset. This effect was also observed for other vocalized emotions (achievement and disgust), but not for affectively neutral vocalizations, and was linked to the perceived arousal of an emotion category. That the timing, polarity, and scalp distribution of this new ERP correlate are similar to ERP markers of emotional face processing suggests that common supramodal brain mechanisms may be involved in the rapid detection of affectively relevant visual and auditory signals.