Article

Neuronal signalling of fear memory.

Department of Psychology and Neuroscience Program, University of Michigan, Ann Arbor, Michigan 48109, USA.
Nature reviews. Neuroscience (Impact Factor: 31.38). 12/2004; 5(11):844-52. DOI: 10.1038/nrn1535
Source: PubMed

ABSTRACT The learning and remembering of fearful events depends on the integrity of the amygdala, but how are fear memories represented in the activity of amygdala neurons? Here, we review recent electrophysiological studies indicating that neurons in the lateral amygdala encode aversive memories during the acquisition and extinction of Pavlovian fear conditioning. Studies that combine unit recording with brain lesions and pharmacological inactivation provide evidence that the lateral amygdala is a crucial locus of fear memory. Extinction of fear memory reduces associative plasticity in the lateral amygdala and involves the hippocampus and prefrontal cortex. Understanding the signalling of aversive memory by amygdala neurons opens new avenues for research into the neural systems that support fear behaviour.

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