Article

Prior cocaine exposure disrupts extinction of fear conditioning.

Program in Neuroscience, University of Maryland School of Medicine, Baltimore, 21230, USA.
Learning &amp Memory (impact factor: 4.22). 13(4):416-21. DOI:10.1101/lm.216206 pp.416-21
Source: PubMed

ABSTRACT Psychostimulant exposure has been shown to cause molecular and cellular changes in prefrontal cortex. It has been hypothesized that these drug-induced changes might affect the operation of prefrontal-limbic circuits, disrupting their normal role in controlling behavior and thereby leading to compulsive drug-seeking. To test this hypothesis, we tested cocaine-treated rats in a fear conditioning, inflation, and extinction task, known to depend on medial prefrontal cortex and amygdala. Cocaine-treated rats conditioned and inflated similar to saline controls but displayed slower extinction learning. These results support the hypothesis that control processes in the medial prefrontal cortex are impaired by cocaine exposure.

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Keywords

amygdala
 
cellular changes
 
cocaine exposure
 
cocaine-treated rats
 
Cocaine-treated rats conditioned
 
compulsive drug-seeking
 
control processes
 
drug-induced changes
 
extinction task
 
fear conditioning
 
medial prefrontal cortex
 
prefrontal cortex
 
prefrontal-limbic circuits
 
Psychostimulant exposure
 
saline controls
 
slower extinction