Thursday, November 15, 2007

ARTICLE UPDATE - Rapid detection of fear in body expressions, an ERP study.

van Heijnsbergen CC, Meeren HK, Grèzes J, de Gelder B.

Brain Research, in press

Recent findings indicate that the perceptual processing of fearful expressions in the face can already be initiated around 100–120 ms after stimulus presentation, demonstrating that emotional information of a face can be encoded before the identity of the face is fully recognized. At present it is not clear whether fear signals from body expressions may be encoded equally as rapid. To answer this question we investigated the early temporal dynamics of perceiving fearful body expression by measuring EEG. Participants viewed images of whole body actions presented either in a neutral or a fearful version. We observed an early emotion effect on the P1 peak latency around 112 ms post stimulus onset hitherto only found for facial expressions. Also consistent with the majority of facial expression studies, the N170 component elicited by perceiving bodies proved not to be sensitive for the expressed fear. In line with previous work, its vertex positive counterpart, the VPP, did show a condition-specific influence for fearful body expression. Our results indicate that the information provided by fearful body expression is already encoded in the early stages of visual processing, and suggest that similar early processing mechanisms are involved in the perception of fear in faces and bodies.

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