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Dopaminergic neurons promote hippocampal reactivation and spatial memory persistence.

ABSTRACT: We found that optogenetic burst stimulation of hippocampal dopaminergic fibers from midbrain neurons in mice exploring novel environments enhanced the reactivation of pyramidal cell assemblies during subsequent sleep/rest. When applied during spatial learning of new goal locations, dopaminergic photostimulation improved the later recall of neural representations of space and stabilized memory performance. These findings reveal that midbrain dopaminergic neurons promote hippocampal network dynamics associated with memory persistence.

SUBMITTER: McNamara CG

PROVIDER: S-EPMC4241115 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Dopaminergic neurons promote hippocampal reactivation and spatial memory persistence.

McNamara Colin G CG Tejero-Cantero Álvaro Á Trouche Stéphanie S Campo-Urriza Natalia N Dupret David D

Nature neuroscience 20141019 12

We found that optogenetic burst stimulation of hippocampal dopaminergic fibers from midbrain neurons in mice exploring novel environments enhanced the reactivation of pyramidal cell assemblies during subsequent sleep/rest. When applied during spatial learning of new goal locations, dopaminergic photostimulation improved the later recall of neural representations of space and stabilized memory performance. These findings reveal that midbrain dopaminergic neurons promote hippocampal network dynami ...[more]

PMID: 25326690

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