Thalamic input to auditory cortex is locally heterogeneous but globally tonotopic

Abstract

Topographic representation of the receptor surface is a fundamental feature of sensory cortical organization. This is imparted by the thalamus, which relays information from the periphery to the cortex. To better understand the rules governing thalamocortical connectivity and the origin of cortical maps, we used in vivo two-photon calcium imaging to characterize the properties of thalamic axons innervating different layers of mouse auditory cortex. Although tonotopically organized at a global level, we found that the frequency selectivity of individual thalamocortical axons is surprisingly heterogeneous, even in layers 3b/4 of the primary cortical areas, where the thalamic input is dominated by the lemniscal projection. We also show that thalamocortical input to layer 1 includes collaterals from axons innervating layers 3b/4 and is largely in register with the main input targeting those layers. Such locally varied thalamocortical projections may be useful in enabling rapid contextual modulation of cortical frequency representations.

Article and author information

Author details

  1. Sebastian A Vasquez-Lopez

    Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4899-1221
  2. Yves Weissenberger

    Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
  3. Michael Lohse

    Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
  4. Peter Keating

    Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0670-9075
  5. Andrew J King

    Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
    Competing interests
    Andrew J King, Senior Editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5180-7179
  6. Johannes C Dahmen

    Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
    For correspondence
    johannes.dahmen@dpag.ox.ac.uk
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9889-8303

Funding

Wellcome (WT07650AIA WT108369/Z/2015/Z)

  • Andrew J King

Wellcome (WT102372)

  • Yves Weissenberger

Clarendon Scholarship, University of Oxford

  • Sebastian A Vasquez-Lopez

Wellcome (WT105241/Z/14/Z)

  • Michael Lohse

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

Reviewing Editor

  1. Christine Petit, Institut Pasteur, France

Publication history

  1. Received: February 11, 2017
  2. Accepted: September 8, 2017
  3. Accepted Manuscript published: September 11, 2017 (version 1)
  4. Version of Record published: September 26, 2017 (version 2)

Copyright

© 2017, Vasquez-Lopez 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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  1. Sebastian A Vasquez-Lopez
  2. Yves Weissenberger
  3. Michael Lohse
  4. Peter Keating
  5. Andrew J King
  6. Johannes C Dahmen
(2017)
Thalamic input to auditory cortex is locally heterogeneous but globally tonotopic
eLife 6:e25141.
https://doi.org/10.7554/eLife.25141
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