ERIC Number: EJ767904
Record Type: Journal
Publication Date: 2006
Pages: 6
Abstractor: Author
ISBN: N/A
ISSN: ISSN-1072-0502
EISSN: N/A
Hippocampal Train Stimulation Modulates Recall of Fear Extinction Independently of Prefrontal Cortex Synaptic Plasticity and Lesions
Garcia, Rene; Farinelli, Melissa; Deschaux, Olivier; Hugues, Sandrine; Thevenet, Aurelie
Learning & Memory, v13 n3 p329-334 May-Jun 2006
It has been shown that long-term potentiation (LTP) develops in the connection between the mediodorsal thalamus (MD) and the medial prefrontal cortex (mPFC) and between the hippocampus (HPC) and the mPFC following fear extinction, and correlates with extinction retention. However, recent lesion studies have shown that combined lesions of the MD and mPFC do not interfere with extinction learning and retention, while inactivation of the dorsal HPC disrupts fear extinction memory. Here we found in rats that immediate post-training HPC low-frequency stimulation (LFS) suppressed extinction-related LTP in the HPC-mPFC pathway and induced difficulties in extinction recall. HPC tetanus, applied several hours later, failed to re-establish mPFC LTP but facilitated recall of extinction. Delayed post-training HPC LFS also provoked mPFC depotentiation and difficulties with extinction recall. HPC tetanus abolished these two effects. We also found that damage to the mPFC induced fear return only in rats that received HPC LFS following extinction training. HPC tetanus also reversed this behavioral effect of HPC LFS in lesioned rats. These data suggest that the HPC interacts with the mPFC during fear extinction, but can modulate fear extinction independently of this interaction. (Contains 5 figures.)
Descriptors: Neurological Impairments, Fear, Recall (Psychology), Animals, Brain Hemisphere Functions, Stimulation
Cold Spring Harbor Laboratory Press. 500 Sunnyside Boulevard, Woodbury, NY 11797-2924. Tel: 800-843-4388; 516-367-8800; Fax: 516-422-4097; e-mail: cshpres@cshl.edu; Web site: http://www.learnmem.org/
Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A