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Hippocampal projections to the anterior olfactory nucleus differentially convey spatiotemporal information during episodic odour memory.

ABSTRACT: The hippocampus is essential for representing spatiotemporal context and establishing its association with the sensory details of daily life to form episodic memories. The olfactory cortex in particular shares exclusive anatomical connections with the hippocampus as a result of their common evolutionary history. Here we selectively inhibit hippocampal projections to the anterior olfactory nucleus (AON) during behavioural tests of contextually cued odour recall. We find that spatial odour memory and temporal odour memory are independently impaired following inhibition of distinct, topographically organized hippocampal-AON pathways. Our results not only reveal a longstanding unknown function for the AON but offer new mechanistic insights regarding the representation of odours in episodic memory.

SUBMITTER: Aqrabawi AJ

PROVIDER: S-EPMC6048034 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Hippocampal projections to the anterior olfactory nucleus differentially convey spatiotemporal information during episodic odour memory.

Aqrabawi Afif J AJ Kim Jun Chul JC

Nature communications 20180716 1

The hippocampus is essential for representing spatiotemporal context and establishing its association with the sensory details of daily life to form episodic memories. The olfactory cortex in particular shares exclusive anatomical connections with the hippocampus as a result of their common evolutionary history. Here we selectively inhibit hippocampal projections to the anterior olfactory nucleus (AON) during behavioural tests of contextually cued odour recall. We find that spatial odour memory ...[more]

PMID: 30013078

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