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Ventro-dorsal Hippocampal Pathway Gates Novelty-Induced Contextual Memory Formation.

ABSTRACT: Novelty facilitates memory formation and is detected by both the dorsal and ventral hippocampus. Although dentate granule cells (GCs) in the dorsal hippocampus are known to mediate the formation of novelty-induced contextual memories, the required pathways and mechanisms remain unclear. Here we demonstrate that a powerful excitatory pathway from mossy cells (MCs) in the ventral hippocampus to dorsal GCs is necessary and sufficient for driving dorsal GC activation in novel environment exploration. In vivo Ca²⁺ imaging in freely moving mice indicated that this pathway relays environmental novelty. Furthermore, manipulation of ventral MC activity bidirectionally regulates novelty-induced contextual memory acquisition. Our results show that ventral MC activity gates contextual memory formation through an intra-hippocampal interaction activated by environmental novelty.

SUBMITTER: Fredes F

PROVIDER: S-EPMC7808756 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Ventro-dorsal Hippocampal Pathway Gates Novelty-Induced Contextual Memory Formation.

Fredes Felipe F Silva Maria Alejandra MA Koppensteiner Peter P Kobayashi Kenta K Joesch Maximilian M Shigemoto Ryuichi R

Current biology : CB 20201015 1

Novelty facilitates memory formation and is detected by both the dorsal and ventral hippocampus. Although dentate granule cells (GCs) in the dorsal hippocampus are known to mediate the formation of novelty-induced contextual memories, the required pathways and mechanisms remain unclear. Here we demonstrate that a powerful excitatory pathway from mossy cells (MCs) in the ventral hippocampus to dorsal GCs is necessary and sufficient for driving dorsal GC activation in novel environment exploration ...[more]

PMID: 33065009

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