Amygdala activity, fear, and anxiety: modulation by stress.

摘要

Over the past approximately 30 years, the neuroscience community has made terrific strides in its understanding of the small region in the temporal lobe named for its peculiar almond shape, the amygdala. This area now provides among the best examples of how neural circuits control specific behaviors. In terms of our depth of understanding of its afferent and efferent connections, the role of incoming signals in modulating emotion-related behavior, and the functional and anatomic results of its projection patterns, the detailed understanding of the amygdala is unsurpassed. Examination of these functions has allowed great progress in dissecting the neural circuitry of emotion regulation. It is involved in many processes, including appetitive behavior (such as affiliation, sex, and drug abuse), but its role as an integral part of the fear circuitry may be the most fully described (1-3). Recent work described in two articles in this issue of Biological Psychiatry (Lazaro-Munoz et al. [4] and Rosenkrantz et al. [5D add to our understanding of the breadth of amygdala function. In particular, how does chronic stress affect amygdala processing, and conversely, how do amygdala-mediated defensive behaviors help protect against stress?