1. Neuroscience
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Neural coding in barrel cortex during whisker-guided locomotion

  1. Nicholas James Sofroniew
  2. Yurii A Vlasov
  3. Samuel Andrew Hires
  4. Jeremy Freeman
  5. Karel Svoboda  Is a corresponding author
  1. Janelia Research Center, Howard Hughes Medical Institute, United States
  2. Janelia Research Campus, Howard Hughes Medical Institute, United States
  3. University of Southern California, United States
Research Article
  • Cited 38
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Cite this article as: eLife 2015;4:e12559 doi: 10.7554/eLife.12559

Abstract

Animals seek out relevant information by moving through a dynamic world, but sensory systems are usually studied under highly constrained and passive conditions that may not probe important dimensions of the neural code. Here we explored neural coding in the barrel cortex of head-fixed mice that tracked walls with their whiskers in tactile virtual reality. Optogenetic manipulations revealed that barrel cortex plays a role in wall-tracking. Closed-loop optogenetic control of layer 4 neurons can substitute for whisker-object contact to guide behavior resembling wall tracking. We measured neural activity using two-photon calcium imaging and extracellular recordings. Neurons were tuned to the distance between the animal snout and the contralateral wall, with monotonic, unimodal, and multimodal tuning curves. This rich representation of object location in the barrel cortex could not be predicted based on simple stimulus-response relationships involving individual whiskers and likely emerges within cortical circuits.

Article and author information

Author details

  1. Nicholas James Sofroniew

    Janelia Research Center, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Yurii A Vlasov

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Samuel Andrew Hires

    Biological Sciences, University of Southern California, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Jeremy Freeman

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Karel Svoboda

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    For correspondence
    svobodak@janelia.hhmi.org
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All procedures were in accordance with protocols approved by the Janelia Institutional Animal Care and Use Committee. (IACUC 14-115)

Reviewing Editor

  1. Sacha B Nelson, Brandeis University, United States

Publication history

  1. Received: October 24, 2015
  2. Accepted: December 21, 2015
  3. Accepted Manuscript published: December 23, 2015 (version 1)
  4. Version of Record published: February 11, 2016 (version 2)

Copyright

© 2015, Sofroniew 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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