Recognition of facial emotion in nine individuals with bilateral amygdala damage

Findings from several case studies have shown that bilateral amygdala damag e impairs recognition of emotions in facial expressions, especially fear. H owever, one study did not find such an impairment, and, in general, compari son across studies has been made difficult because of the different stimuli and tasks employed. In a collaborative study to facilitate such comparison s, we report here the recognition of emotional facial expressions in nine s ubjects with bilateral amygdala damage, using a sensitive and quantitative assessment. Compared to controls, the subjects as a group were significantl y impaired in recognizing fear, although individual performances ranged fro m severely impaired to essentially normal. Most subjects were impaired on s everal negative emotions in addition to fear, but no subject was impaired i n recognizing happy expressions. An analysis of response consistency showed that impaired recognition of fear could not be attributed simply to mistak ing fear for another emotion. While it remains unclear why some subjects wi th amygdala damage included here are not impaired on our task, the results overall are consistent with the idea that the amygdala plays an important r ole in triggering knowledge related to threat and danger signaled by facial expressions. (C) 1999 Elsevier Science Ltd. All rights reserved.