The organizational principles of de-differentiated topographic maps in somatosensory cortex

  1. Peng Liu
  2. Anastasia Chrysidou
  3. Juliane Doehler
  4. Martin Hebart
  5. Thomas Wolbers
  6. Esther Kuehn  Is a corresponding author
  1. Otto-von-Guericke University Magdeburg, Germany
  2. Max Planck Institute for Human Cognitive and Brain Sciences, Germany
  3. German Center for Neurodegenerative Diseases (DZNE), Germany

Abstract

Topographic maps are a fundamental feature of cortex architecture in the mammalian brain. One common theory is that the de-differentiation of topographic maps links to impairments in everyday behavior due to less precise functional map readouts. Here, we tested this theory by characterizing de-differentiated topographic maps in primary somatosensory cortex (SI) of younger and older adults by means of ultra-high resolution functional magnetic resonance imaging together with perceptual finger individuation and hand motor performance. Older adults' SI maps showed similar amplitude and size to younger adults' maps, but presented with less representational similarity between distant fingers. Larger population receptive field sizes in older adults' maps did not correlate with behavior, whereas reduced cortical distances between D2 and D3 related to worse finger individuation but better motor performance. Our data uncover the drawbacks of a simple de-differentiation model of topographic map function, and motivate the introduction of feature-based models of cortical reorganization.

Data availability

Behavioral and MRI data have been deposited in dryad (doi:10.5061/dryad.mgqnk98x8)

The following data sets were generated

Article and author information

Author details

  1. Peng Liu

    Institute for Cognitive Neurology and Dementia Research, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Anastasia Chrysidou

    Institute for Cognitive Neurology and Dementia Research, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Juliane Doehler

    Institute for Cognitive Neurology and Dementia Research, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Martin Hebart

    Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Thomas Wolbers

    RG Aging & Cognition, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Esther Kuehn

    Institute for Cognitive Neurology and Dementia Research, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
    For correspondence
    esther.kuehn@dzne.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3169-1951

Funding

Center for Behavioral Brain Sciences (ESIF/EFRE 2014-2020; FKZ: ZS/2016/04/78113)

  • Esther Kuehn

German Research Foundation (KU 3711/2-1,project number: 423633679)

  • Peng Liu
  • Juliane Doehler

Else Kroener Fresenius Stiftung (2019-A03)

  • Anastasia Chrysidou

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

Ethics

Human subjects: All participants were paid for their attendance and written informed consent for participation and data handling was received from all participants before starting the experiment. The study was approved by the Ethics committee of the Otto-von-Guericke University Magdeburg (68/16).

Reviewing Editor

  1. Peter Kok, University College London, United Kingdom

Publication history

  1. Received: June 16, 2020
  2. Accepted: May 17, 2021
  3. Accepted Manuscript published: May 18, 2021 (version 1)
  4. Version of Record published: June 8, 2021 (version 2)

Copyright

© 2021, Liu 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. Peng Liu
  2. Anastasia Chrysidou
  3. Juliane Doehler
  4. Martin Hebart
  5. Thomas Wolbers
  6. Esther Kuehn
(2021)
The organizational principles of de-differentiated topographic maps in somatosensory cortex
eLife 10:e60090.
https://doi.org/10.7554/eLife.60090

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