1. Neuroscience
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Thalamic reticular nucleus induces fast and local modulation of arousal state

  1. Laura D Lewis
  2. Jakob Voigts
  3. Francisco J Flores
  4. Lukas I Schmitt
  5. Matthew A Wilson
  6. Michael M Halassa
  7. Emery N Brown  Is a corresponding author
  1. Harvard University, United States
  2. Massachusetts Institute of Technology, United States
  3. New York University, United States
Research Article
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Cite this article as: eLife 2015;4:e08760 doi: 10.7554/eLife.08760

Abstract

During low arousal states such as drowsiness and sleep, cortical neurons exhibit rhythmic slow wave activity associated with periods of neuronal silence. Slow waves are locally regulated, and local slow wave dynamics are important for memory, cognition, and behaviour. While several brainstem structures for controlling global sleep states have now been well characterized, a mechanism underlying fast and local modulation of cortical slow waves has not been identified. Here, using optogenetics and whole cortex electrophysiology, we show that local tonic activation of thalamic reticular nucleus (TRN) rapidly induces slow wave activity in a spatially restricted region of cortex. These slow waves resemble those seen in sleep, as cortical units undergo periods of silence phase-locked to the slow wave. Furthermore, animals exhibit behavioural changes consistent with a decrease in arousal state during TRN stimulation. We conclude that TRN can induce rapid modulation of local cortical state.

Article and author information

Author details

  1. Laura D Lewis

    Society of Fellows, Harvard University, Cambridge, United States
    Competing interests
    No competing interests declared.
  2. Jakob Voigts

    Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
    Competing interests
    No competing interests declared.
  3. Francisco J Flores

    Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
    Competing interests
    No competing interests declared.
  4. Lukas I Schmitt

    Neuroscience Institute, New York University, New York, United States
    Competing interests
    No competing interests declared.
  5. Matthew A Wilson

    Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
    Competing interests
    No competing interests declared.
  6. Michael M Halassa

    Neuroscience Institute, New York University, New York, United States
    Competing interests
    No competing interests declared.
  7. Emery N Brown

    Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
    For correspondence
    enb@neurostat.mit.edu
    Competing interests
    Emery N Brown, Reviewing editor, eLife.

Ethics

Animal experimentation: All experimental procedures were approved by the MIT Committee on Animal Care (protocol number #0514-038-17).

Reviewing Editor

  1. Michael J Frank, Brown University, United States

Publication history

  1. Received: May 15, 2015
  2. Accepted: September 24, 2015
  3. Accepted Manuscript published: October 13, 2015 (version 1)
  4. Version of Record published: December 9, 2015 (version 2)

Copyright

© 2015, Lewis 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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