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Synaptic representation of locomotion in single cerebellar granule cells

  1. Kate Powell
  2. Alexandre Mathy
  3. Ian Duguid
  4. Michael Häusser  Is a corresponding author
  1. University College London, United Kingdom
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Cite this article as: eLife 2015;4:e07290 doi: 10.7554/eLife.07290

Abstract

The cerebellum plays a crucial role in the regulation of locomotion, but how movement is represented at the synaptic level is not known. Here, we use in vivo patch-clamp recordings to show that locomotion can be directly read out from mossy fiber synaptic input and spike output in single granule cells. The increase in granule cell spiking during locomotion is enhanced by glutamate spillover currents recruited during movement. Surprisingly, the entire step sequence can be predicted from input EPSCs and output spikes of a single granule cell, suggesting that a robust gait code is present already at the cerebellar input layer and transmitted via the granule cell pathway to downstream Purkinje cells. Thus, synaptic input delivers remarkably rich information to single neurons during locomotion.

Article and author information

Author details

  1. Kate Powell

    Wolfson Institute for Biomedical Research and Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  2. Alexandre Mathy

    Wolfson Institute for Biomedical Research and Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  3. Ian Duguid

    Wolfson Institute for Biomedical Research and Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  4. Michael Häusser

    Wolfson Institute for Biomedical Research and Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
    For correspondence
    m.hausser@ucl.ac.uk
    Competing interests
    Michael Häusser, Reviewing editor, eLife.

Ethics

Animal experimentation: This study was performed in strict accordance with UK Home Office regulations. Experiments were carried out under Project Licence 70/7833 issued by the Home Office, which was issued following local ethical review, and under the relevant Personal Licences issued by the Home Office. All surgery was performed under isoflurane anesthesia, and every effort was made to minimize suffering.

Reviewing Editor

  1. Indira M Raman, Northwestern University, United States

Publication history

  1. Received: March 3, 2015
  2. Accepted: June 16, 2015
  3. Accepted Manuscript published: June 17, 2015 (version 1)
  4. Version of Record published: July 13, 2015 (version 2)

Copyright

© 2015, Powell 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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