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Reminders reinstate context-specificity to generalized remote memories in rats: relation to activity in the hippocampus and aCC.

ABSTRACT: Conditioned fear memories that are context-specific shortly after conditioning generalize over time. We exposed rats to a context reminder 30 d after conditioning, which served to reinstate context-specificity, and investigated how this reminder alters retrieval-induced activity in the hippocampus and anterior cingulate cortex (aCC) relative to a no reminder condition. c-Fos expression in dorsal CA1 was observed following retrieval in the original context, but not in a novel context, whether or not the memory was reactivated, suggesting that dCA1 retains the context-specific representation. c-Fos was highly expressed in aCC following remote memory testing in both contexts, regardless of reminder condition, indicating that aCC develops generalized representations that are insensitive to memory reactivation.

SUBMITTER: Sekeres MJ

PROVIDER: S-EPMC6919192 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Reminders reinstate context-specificity to generalized remote memories in rats: relation to activity in the hippocampus and aCC.

Sekeres Melanie J MJ Moscovitch Morris M Grady Cheryl L CL Sullens D Gregory DG Winocur Gordon G

Learning & memory (Cold Spring Harbor, N.Y.) 20191216 1

Conditioned fear memories that are context-specific shortly after conditioning generalize over time. We exposed rats to a context reminder 30 d after conditioning, which served to reinstate context-specificity, and investigated how this reminder alters retrieval-induced activity in the hippocampus and anterior cingulate cortex (aCC) relative to a no reminder condition. c-Fos expression in dorsal CA1 was observed following retrieval in the original context, but not in a novel context, whether or ...[more]

PMID: 31843976

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