Author:
Lebrón Kelimer,Milad Mohammed R.,Quirk Gregory J.
Abstract
Extinction of auditory fear conditioning is thought to form a new memory.
We previously found that rats with vmPFC lesions could extinguish fear to the
tone within a session, but showed no recall of extinction 24 h later. One
interpretation is that the vmPFC is the sole storage site of extinction
memory. However, it is also possible that lesioned rats were unable to
retrieve extinction memory stored in other structures. To determine if a
latent extinction memory could be retrieved with additional training, we
repeated the experiment but added an additional 5 d of extinction reminder
trials. Replicating our previous findings, vmPFC-lesioned rats extinguished
normally on day 1, but showed no recall of extinction on day 2. Over the next
5 d, however, lesioned rats showed significant savings in their rate of
re-extinction. Thus, the vmPFC is not the only site where extinction memory is
stored. Nevertheless, lesioned rats receiving only two extinction trials per
day required twice as many days to initiate extinction as controls. Although
recall of extinction is possible without the vmPFC, it is significantly
delayed. We suggest that the vmPFC accelerates extinction by permitting access
to recently learned extinction trials, thereby maximizing behavioral
flexibility.
Publisher
Cold Spring Harbor Laboratory
Subject
Cellular and Molecular Neuroscience,Cognitive Neuroscience,Neuropsychology and Physiological Psychology
Cited by
173 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献