Neuron
Volume 53, Issue 6, 15 March 2007, Pages 871-880
Journal home page for Neuron

Article
Consolidation of Fear Extinction Requires NMDA Receptor-Dependent Bursting in the Ventromedial Prefrontal Cortex

https://doi.org/10.1016/j.neuron.2007.02.021Get rights and content
Under an Elsevier user license
open archive

Summary

Extinction of conditioned fear is an active learning process requiring N-methyl-D-aspartate receptors (NMDARs), but the timing, location, and neural mechanisms of NMDAR-mediated processing in extinction are a matter of debate. Here we show that infusion of the NMDAR antagonist CPP into the ventromedial prefrontal cortex (vmPFC) prior to, or immediately after, extinction training impaired 24 hr recall of extinction. These findings indicate that consolidation of extinction requires posttraining activation of NMDARs within the vmPFC. Using multichannel unit recording, we observed that CPP selectively reduced burst firing in vmPFC neurons, suggesting that bursting in vmPFC is necessary for consolidation of extinction. In support of this, we found that the degree of bursting in infralimbic vmPFC neurons shortly after extinction predicted subsequent recall of extinction. We suggest that NMDAR-dependent bursting in the infralimbic vmPFC initiates calcium-dependent molecular cascades that stabilize extinction memory, thereby allowing for successful recall of extinction.

SYSNEURO
PROTEINS
HUMDISEASE

Cited by (0)

2

Present address: Department of Psychiatry, University of Puerto Rico School of Medicine, P.O. Box 365067, San Juan, Puerto Rico 00936-5067.

3

These authors contributed equally to this work.