The amygdala has long been known to play a central role in the acquisition and expression
of fear. More recently, convergent evidence has implicated the amygdala in the extinction
of fear as well. In rodents, some of this evidence comes from the infusion of drugs
directly into the amygdala and, in particular, into the basolateral complex of the
amygdala, during or after extinction learning. In vivo electrophysiology has identified
cellular correlates of extinction learning and memory in the lateral nucleus of that
structure. Human imaging experiments also indicate that amygdaloid activity correlates
with extinction training. In addition, some studies have directly identified changes
in molecular constituents of the basolateral amygdala. Together these experiments
strongly indicate that the basolateral amygdala plays a crucial role in extinction
learning. Interpreted in the light of these findings, several recent in vitro electrophysiology
studies in amygdala-containing brain slices are suggestive of potential synaptic and
circuit bases of extinction learning.
Key Words
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Article info
Publication history
Accepted:
May 12,
2006
Received in revised form:
March 28,
2006
Received:
August 29,
2005
Identification
Copyright
© 2006 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
