A Neural Switch for Active and Passive Fear.
Neuron. 2010 Aug 26;67(4):656-666
Authors: Gozzi A, Jain A, Giovanelli A, Bertollini C, Crestan V, Schwarz AJ, Tsetsenis T, Ragozzino D, Gross CT, Bifone A
The central nucleus of the amygdala (CeA) serves as a major output of this structure and plays a critical role in the expression of conditioned fear. By combining cell- and tissue-specific pharmacogenetic inhibition with functional magnetic resonance imaging (fMRI), we identified circuits downstream of CeA that control fear expression in mice. Selective inhibition of a subset of neurons in CeA led to decreased conditioned freezing behavior and increased cortical arousal as visualized by fMRI. Correlation analysis of fMRI signals identified functional connectivity between CeA, cholinergic forebrain nuclei, and activated cortical structures, and cortical arousal was blocked by cholinergic antagonists. Importantly, inhibition of these neurons switched behavioral responses to the fear stimulus from passive to active responses. Our findings identify a neural circuit in CeA that biases fear responses toward either passive or active coping strategies.
PMID: 20797541 [PubMed - as supplied by publisher]