Format

Send to

Choose Destination
Neuron. 2017 Nov 15;96(4):925-935.e6. doi: 10.1016/j.neuron.2017.09.035. Epub 2017 Oct 19.

Task Demands Predict a Dynamic Switch in the Content of Awake Hippocampal Replay.

Author information

1
Research Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK. Electronic address: h.olafsdottir@ucl.ac.uk.
2
Research Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK; Institute of Neurology, UCL, Queen Square, London WC1N 3BQ, UK.
3
Research Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK. Electronic address: caswell.barry@ucl.ac.uk.

Abstract

Reactivation of hippocampal place cell sequences during behavioral immobility and rest has been linked with both memory consolidation and navigational planning. Yet it remains to be investigated whether these functions are temporally segregated, occurring during different behavioral states. During a self-paced spatial task, awake hippocampal replay occurring either immediately before movement toward a reward location or just after arrival at a reward location preferentially involved cells consistent with the current trajectory. In contrast, during periods of extended immobility, no such biases were evident. Notably, the occurrence of task-focused reactivations predicted the accuracy of subsequent spatial decisions. Additionally, during immobility, but not periods preceding or succeeding movement, grid cells in deep layers of the entorhinal cortex replayed coherently with the hippocampus. Thus, hippocampal reactivations dynamically and abruptly switch between operational modes in response to task demands, plausibly moving from a state favoring navigational planning to one geared toward memory consolidation.

KEYWORDS:

entorhinal cortex; grid cell; hippocampus; memory consolidation; navigation; place cell; planning; replay

PMID:
29056296
PMCID:
PMC5697915
DOI:
10.1016/j.neuron.2017.09.035
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center