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Electrical synapses control hippocampal contributions to fear learning and memory.

ABSTRACT: The role of electrical synapses in synchronizing neuronal assemblies in the adult mammalian brain is well documented. However, their role in learning and memory processes remains unclear. By combining Pavlovian fear conditioning, activity-dependent immediate early gene expression, and in vivo electrophysiology, we discovered that blocking neuronal gap junctions within the dorsal hippocampus impaired context-dependent fear learning, memory, and extinction. Theta rhythms in freely moving rats were also disrupted. Our results show that gap junction-mediated neuronal transmission is a prominent feature underlying emotional memories.

SUBMITTER: Bissiere S

PROVIDER: S-EPMC4276370 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Electrical synapses control hippocampal contributions to fear learning and memory.

Bissiere Stephanie S Zelikowsky Moriel M Ponnusamy Ravikumar R Jacobs Nathan S NS Blair Hugh T HT Fanselow Michael S MS

Science (New York, N.Y.) 20110101 6013

The role of electrical synapses in synchronizing neuronal assemblies in the adult mammalian brain is well documented. However, their role in learning and memory processes remains unclear. By combining Pavlovian fear conditioning, activity-dependent immediate early gene expression, and in vivo electrophysiology, we discovered that blocking neuronal gap junctions within the dorsal hippocampus impaired context-dependent fear learning, memory, and extinction. Theta rhythms in freely moving rats were ...[more]

PMID: 21212357

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