1. Neuroscience
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mPFC spindle cycles organize sparse thalamic activation and recently active CA1 cells during non-REM sleep

  1. Carmen Varela  Is a corresponding author
  2. Matthew A Wilson  Is a corresponding author
  1. Florida Atlantic University, United States
  2. Massachusetts Institute of Technology, United States
Research Article
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Cite this article as: eLife 2020;9:e48881 doi: 10.7554/eLife.48881


Sleep oscillations in the neocortex and hippocampus are critical for the integration of new memories into stable generalized representations in neocortex. However, the role of the thalamus in this process is poorly understood. To determine the thalamic contribution to non-REM oscillations (sharp-wave ripples, SWRs; slow/delta; spindles), we recorded units and local field potentials (LFPs) simultaneously in the limbic thalamus, mPFC, and CA1 in rats. We report that the cycles of neocortical spindles provide a key temporal window that coordinates CA1 SWRs with sparse but consistent activation of thalamic units. Thalamic units were phase-locked to delta and spindles in mPFC, and fired at consistent lags with other thalamic units within spindles, while CA1 units that were active during spatial exploration were engaged in SWR-coupled spindles after behavior. The sparse thalamic firing could promote an incremental integration of recently acquired memory traces into neocortical schemas through the interleaved activation of thalamocortical cells.

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Author details

  1. Carmen Varela

    Psychology, Florida Atlantic University, Jupiter, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0398-2567
  2. Matthew A Wilson

    Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.


Caja Madrid Foundation (Convocatoria 2008)

  • Carmen Varela

Brain & Behavior Research Foundation (22852)

  • Carmen Varela

NSF STC award CCF-1231216 (CCF-1231216)

  • Matthew A Wilson

NIH grant TR01-GM10498 (TR01-GM10498)

  • Matthew A Wilson

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Laura L Colgin, University of Texas at Austin, United States

Publication history

  1. Received: May 29, 2019
  2. Accepted: June 11, 2020
  3. Accepted Manuscript published: June 11, 2020 (version 1)
  4. Version of Record published: June 26, 2020 (version 2)


© 2020, Varela & Wilson

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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