A differential neural response in the human amygdala to fearful and happy facial expressions
Abstract
THE amygdala is thought to play a crucial role in emotional and social behaviour1. Animal studies implicate the amygdala in both fear conditioning2 and face perception3. In humans, lesions of the amygdala can lead to selective deficits in the recognition of fearful facial expressions4,5 and impaired fear conditioning6,7, and direct electrical stimulation evokes fearful emotional responses8. Here we report direct in vivo evidence of a differential neural response in the human amygdala to facial expressions of fear and happiness. Positron-emission tomography (PET) measures of neural activity were acquired while subjects viewed photographs of fearful or happy faces, varying systematically in emotional intensity. The neuronal response in the left amygdala was significantly greater to fearful as opposed to happy expressions. Furthermore, this response showed a significant interaction with the intensity of emotion (increasing with increasing fearfulness, decreasing with increasing happiness). The findings provide direct evidence that the human amygdala is engaged in processing the emotional salience of faces, with a specificity of response to fearful facial expressions.
- Publication:
-
Nature
- Pub Date:
- October 1996
- DOI:
- 10.1038/383812a0
- Bibcode:
- 1996Natur.383..812M