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Adult-born neurons add flexibility to hippocampal memories

Although most neurons are generated embryonically, neurogenesis is maintained at low rates in specific brain areas throughout adulthood, including the dentate gyrus of the mammalian hippocampus. Episodic-like memories encoded in the hippocampus require the dentate gyrus to decorrelate similar experi...

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Autores principales: Fölsz, Orsolya, Trouche, Stéphanie, Croset, Vincent
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9975346/
https://www.ncbi.nlm.nih.gov/pubmed/36875670
http://dx.doi.org/10.3389/fnins.2023.1128623
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author Fölsz, Orsolya
Trouche, Stéphanie
Croset, Vincent
author_facet Fölsz, Orsolya
Trouche, Stéphanie
Croset, Vincent
author_sort Fölsz, Orsolya
collection PubMed
description Although most neurons are generated embryonically, neurogenesis is maintained at low rates in specific brain areas throughout adulthood, including the dentate gyrus of the mammalian hippocampus. Episodic-like memories encoded in the hippocampus require the dentate gyrus to decorrelate similar experiences by generating distinct neuronal representations from overlapping inputs (pattern separation). Adult-born neurons integrating into the dentate gyrus circuit compete with resident mature cells for neuronal inputs and outputs, and recruit inhibitory circuits to limit hippocampal activity. They display transient hyperexcitability and hyperplasticity during maturation, making them more likely to be recruited by any given experience. Behavioral evidence suggests that adult-born neurons support pattern separation in the rodent dentate gyrus during encoding, and they have been proposed to provide a temporal stamp to memories encoded in close succession. The constant addition of neurons gradually degrades old connections, promoting generalization and ultimately forgetting of remote memories in the hippocampus. This makes space for new memories, preventing saturation and interference. Overall, a small population of adult-born neurons appears to make a unique contribution to hippocampal information encoding and removal. Although several inconsistencies regarding the functional relevance of neurogenesis remain, in this review we argue that immature neurons confer a unique form of transience on the dentate gyrus that complements synaptic plasticity to help animals flexibly adapt to changing environments.
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spelling pubmed-99753462023-03-02 Adult-born neurons add flexibility to hippocampal memories Fölsz, Orsolya Trouche, Stéphanie Croset, Vincent Front Neurosci Neuroscience Although most neurons are generated embryonically, neurogenesis is maintained at low rates in specific brain areas throughout adulthood, including the dentate gyrus of the mammalian hippocampus. Episodic-like memories encoded in the hippocampus require the dentate gyrus to decorrelate similar experiences by generating distinct neuronal representations from overlapping inputs (pattern separation). Adult-born neurons integrating into the dentate gyrus circuit compete with resident mature cells for neuronal inputs and outputs, and recruit inhibitory circuits to limit hippocampal activity. They display transient hyperexcitability and hyperplasticity during maturation, making them more likely to be recruited by any given experience. Behavioral evidence suggests that adult-born neurons support pattern separation in the rodent dentate gyrus during encoding, and they have been proposed to provide a temporal stamp to memories encoded in close succession. The constant addition of neurons gradually degrades old connections, promoting generalization and ultimately forgetting of remote memories in the hippocampus. This makes space for new memories, preventing saturation and interference. Overall, a small population of adult-born neurons appears to make a unique contribution to hippocampal information encoding and removal. Although several inconsistencies regarding the functional relevance of neurogenesis remain, in this review we argue that immature neurons confer a unique form of transience on the dentate gyrus that complements synaptic plasticity to help animals flexibly adapt to changing environments. Frontiers Media S.A. 2023-02-15 /pmc/articles/PMC9975346/ /pubmed/36875670 http://dx.doi.org/10.3389/fnins.2023.1128623 Text en Copyright © 2023 Fölsz, Trouche and Croset. https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Neuroscience
Fölsz, Orsolya
Trouche, Stéphanie
Croset, Vincent
Adult-born neurons add flexibility to hippocampal memories
title Adult-born neurons add flexibility to hippocampal memories
title_full Adult-born neurons add flexibility to hippocampal memories
title_fullStr Adult-born neurons add flexibility to hippocampal memories
title_full_unstemmed Adult-born neurons add flexibility to hippocampal memories
title_short Adult-born neurons add flexibility to hippocampal memories
title_sort adult-born neurons add flexibility to hippocampal memories
topic Neuroscience
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9975346/
https://www.ncbi.nlm.nih.gov/pubmed/36875670
http://dx.doi.org/10.3389/fnins.2023.1128623
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