Format

Send to

Choose Destination
Behav Neurosci. 1993 Dec;107(6):1093-8.

Effects of amygdala, hippocampus, and periaqueductal gray lesions on short- and long-term contextual fear.

Author information

1
Neuroscience Program, University of Southern California, Los Angeles.

Abstract

The effects of amygdala, hippocampus, and periaqueductal gray (PAG) lesions on contextual fear conditioning in rats were examined. Freezing behavior served as the measure of conditioning. Unlesioned control animals showed reliable conditional freezing in the testing chamber when observed both immediately and 24 hr after footshocks. In contrast, rats with amygdala or ventral PAG lesions exhibited a significant attenuation in freezing both immediately and 24 hr after the shocks. Dorsal PAG lesions had no effect on freezing at either time. Animals with hippocampal lesions displayed robust freezing behavior immediately following the shock, even though they showed a marked deficit in freezing 24 hr after the shock. These results indicate that there are anatomically dissociable short- and long-term conditional fear states.

PMID:
8136063
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for American Psychological Association
Loading ...
Support Center