Distinct hippocampal-cortical memory representations for experiences associated with movement versus immobility
- University of California San Francisco, United States
- University of California Berkeley, United States
- Princeton University, United States
Abstract
While ongoing experience proceeds continuously, memories of past experience are often recalled as episodes with defined beginnings and ends. The neural mechanisms that lead to the formation of discrete episodes from the stream of neural activity patterns representing ongoing experience are unknown. To investigate these mechanisms, we recorded neural activity in the rat hippocampus and prefrontal cortex, structures critical for memory processes. We show that during spatial navigation, hippocampal CA1 place cells maintain a continuous spatial representation across different states of motion (movement and immobility). In contrast, during sharp-wave ripples (SWRs), when representations of experience are transiently reactivated from memory, movement- and immobility-associated activity patterns are most often reactivated separately. Concurrently, distinct hippocampal reactivations of movement- or immobility-associated representations are accompanied by distinct modulation patterns in prefrontal cortex. These findings demonstrate a continuous representation of ongoing experience can be separated into independently reactivated memory representations.
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Author details
Funding
National Institute of Mental Health (RO1MH105174)
- Jai Y Yu
- Kenneth Kay
- Daniel F Liu
- Marielena Sosa
- Jason E Chung
- Loren M Frank
Jane Coffin Childs Memorial Fund for Medical Research
- Jai Y Yu
University of California (LF-12-237680)
- Loren M Frank
Howard Hughes Medical Institute
- Jai Y Yu
- Kenneth Kay
- Loren M Frank
National Institute of Mental Health (R01MH097084)
- Loren M Frank
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments were conducted in accordance with University of California San Francisco Institutional Animal Care and Use Committee and US National Institutes of Health guidelines. The protocol was approved by the Institutional Animal Care and Use Committee, approval number AN110101-03B. All surgical procedures were performed under anesthesia and every effort was made to minimize suffering.
Copyright
© 2017, Yu 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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Distinct hippocampal-cortical memory representations for experiences associated with movement versus immobility
eLife 6:e27621.
https://doi.org/10.7554/eLife.27621
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