Multiple time-scales of decision making in the hippocampus and prefrontal cortex
Abstract
The prefrontal cortex and hippocampus are crucial for memory-guided decision-making. Neural activity in the hippocampus exhibits place-cell sequences at multiple timescales, including slow behavioral sequences (~seconds) and fast theta sequences (~100-200 ms) within theta oscillation cycles. How prefrontal ensembles interact with hippocampal sequences to support decision-making is unclear. Here, we examined simultaneous hippocampal and prefrontal ensemble activity in rats during learning of a spatial working-memory decision task. We found clear theta sequences in prefrontal cortex, nested within its behavioral sequences. In both regions, behavioral sequences maintained representations of current choices during navigation. In contrast, hippocampal theta sequences encoded alternatives for deliberation, and were coordinated with prefrontal theta sequences that predicted upcoming choices. During error trials, these representations were preserved to guide ongoing behavior, whereas replay sequences during inter-trial periods were impaired prior to navigation. These results establish cooperative interaction between hippocampal and prefrontal sequences at multiple timescales for memory-guided decision-making.
Data availability
All data generated or analysed during this study are included in the manuscript and source data files.
Article and author information
Author details
Funding
National Institutes of Health (R01 MH112661)
- Shantanu P Jadhav
Richard and Susan Smith Family Foundation (Odyssey award)
- Shantanu P Jadhav
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Laura L. Colgin
Ethics
Animal experimentation: All procedures were approved by the Institutional Animal Care and Use Committee at Brandeis University (protocol # 21001) and conformed to US National Institutes of Health guidelines.
Version history
- Received: January 4, 2021
- Accepted: March 5, 2021
- Accepted Manuscript published: March 8, 2021 (version 1)
- Version of Record published: March 25, 2021 (version 2)
Copyright
© 2021, Tang et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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