Format

Send to

Choose Destination
Sci Rep. 2015 Feb 11;5:8388. doi: 10.1038/srep08388.

Fear renewal preferentially activates ventral hippocampal neurons projecting to both amygdala and prefrontal cortex in rats.

Author information

1
Department of Psychology and Institute for Neuroscience, Texas A&M University, College Station, Texas 77843 USA.

Abstract

Anxiety, trauma and stress-related disorders are often characterized by a loss of context-appropriate emotional responding. The contextual retrieval of emotional memory involves hippocampal projections to the medial prefrontal cortex and amygdala; however the relative contribution of these projections is unclear. To address this question, we characterized retrieval-induced Fos expression in ventral hippocampal (VH) neurons projecting to the prelimbic cortex (PL) and basal amygdala (BA) after the extinction of conditioned fear in rats. After extinction, freezing behavior (an index of learned fear) to the auditory conditioned stimulus was suppressed in the extinction context, but was "renewed" in another context. Hippocampal neurons projecting to either PL or BA exhibited similar degrees of context-dependent Fos expression; there were more Fos-positive neurons in each area after the renewal, as opposed, to suppression of fear. Importantly, however, VH neurons projecting to both PL and BA were more likely to express Fos during fear renewal than neurons projecting to either PL or BA alone. These data suggest that although projections from the hippocampus to PL and BA are similarly involved in the contextual retrieval of emotional memories, VH neurons with collaterals to both areas may be particularly important for synchronizing prefrontal-amygdala circuits during fear renewal.

PMID:
25669753
PMCID:
PMC4323647
DOI:
10.1038/srep08388
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center