The Human Amygdala and the Induction and Experience of Fear
Current Biology, 16 December 2010
Copyright © 2011 Elsevier Ltd All rights reserved.
10.1016/j.cub.2010.11.042

Authors
Justin S. Feinstein, Ralph Adolphs, Antonio Damasio, Daniel TranelSee Affiliations

Highlights

-Case study of patient SM, a rare human patient with focal bilateral amygdala lesions
-First investigation of the induction and experience of fear in such a patient
-SM failed to exhibit fear behaviors, and her fear experience was highly impoverished
-The human amygdala plays a pivotal role in triggering a state of fear

Summary

Although clinical observations suggest that humans with amygdala damage have abnormal fear reactions and a reduced experience of fear [1,2,3], these impressions have not been systematically investigated. To address this gap, we conducted a new study in a rare human patient, SM, who has focal bilateral amygdala lesions [4]. To provoke fear in SM, we exposed her to live snakes and spiders, took her on a tour of a haunted house, and showed her emotionally evocative films. On no occasion did SM exhibit fear, and she never endorsed feeling more than minimal levels of fear. Likewise, across a large battery of self-report questionnaires, 3 months of real-life experience sampling, and a life history replete with traumatic events, SM repeatedly demonstrated an absence of overt fear manifestations and an overall impoverished experience of fear. Despite her lack of fear, SM is able to exhibit other basic emotions and experience the respective feelings. The findings support the conclusion that the human amygdala plays a pivotal role in triggering a state of fear and that the absence of such a state precludes the experience of fear itself. (cont...)

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