Medial prefrontal cortex activation facilitates re-extinction of fear in rats
- 1Department of Psychology, University of Michigan, Ann Arbor, Michigan 48109-1043, USA
- 2Neuroscience Program, University of Michigan, Ann Arbor, Michigan 48109-1043, USA
Abstract
It has been suggested that reduced infralimbic (IL) cortical activity contributes to impairments of fear extinction. We therefore explored whether pharmacological activation of the IL would facilitate extinction under conditions it normally fails (i.e., immediate extinction). Rats received auditory fear conditioning 1 h before extinction training. Immediately prior to extinction, rats received microinfusions into the IL of the GABAA receptor antagonist, picrotoxin, or the NMDA receptor partial agonist, D-cycloserine. Although neither drug facilitated extinction, they both facilitated the subsequent re-extinction of fear when animals were trained in a drug-free state, suggesting that activating the IL primes behavioral extinction.
Footnotes
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↵3 Corresponding author.
E-mail maren{at}umich.edu; fax (734) 763-7480.
- Received November 4, 2010.
- Accepted January 13, 2011.
- © 2011 Cold Spring Harbor Laboratory Press
