Finger somatotopy is preserved after tetraplegia but deteriorates over time

  1. Sanne Kikkert  Is a corresponding author
  2. Dario Pfyffer
  3. Michaela Verling
  4. Patrick Freund
  5. Nicole Wenderoth
  1. ETH Zürich, Switzerland
  2. University of Zürich, Switzerland

Abstract

Previous studies showed reorganised and/or altered activity in the primary sensorimotor cortex after a spinal cord injury (SCI), suggested to reflect abnormal processing. However, little is known about whether somatotopically-specific representations can be activated despite reduced or absent afferent hand inputs. In this observational study we used functional MRI and an (attempted) finger movement task in tetraplegic patients to characterise the somatotopic hand layout in primary somatosensory cortex. We further used structural MRI to assess spared spinal tissue bridges. We found that somatotopic hand representations can be activated through attempted finger movements in absence of sensory and motor hand functioning, and no spared spinal tissue bridges. Such preserved hand somatotopy could be exploited by rehabilitation approaches that aim to establish new hand-brain functional connections after SCI (e.g., neuroprosthetics). However, over years since SCI the hand representation somatotopy deteriorated, suggesting that somatotopic hand representations are more easily targeted within the first years after SCI.

Data availability

Full details of the experimental protocol are available on clinicaltrials.gov under the number NCT03772548. Data is shared on https://osf.io/e8u95/.

Article and author information

Author details

  1. Sanne Kikkert

    Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland
    For correspondence
    sanne.kikkert@hest.ethz.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9952-4864
  2. Dario Pfyffer

    Spinal Cord Injury Center, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2406-9251
  3. Michaela Verling

    Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Patrick Freund

    Spinal Cord Injury Center, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4851-2246
  5. Nicole Wenderoth

    Neural Control of Movement Lab, ETH Zürich, Zürich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3246-9386

Funding

Swiss National Science Foundation (SNF 320030_175616)

  • Nicole Wenderoth

ETH Zurich Postdoctoral Fellowship Program

  • Sanne Kikkert

Swiss National Science Foundation (PCEFP3_181362 / 1)

  • Patrick Freund

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

Reviewing Editor

  1. J Andrew Pruszynski, Western University, Canada

Ethics

Human subjects: Participants' informed consent was obtained according to the Declaration of Helsinki prior to study onset. Ethical approval was granted by the Kantonale Ethikkommission Zürich (EK-2018-00937).

Version history

  1. Preprint posted: February 9, 2021 (view preprint)
  2. Received: February 19, 2021
  3. Accepted: October 18, 2021
  4. Accepted Manuscript published: October 19, 2021 (version 1)
  5. Version of Record published: November 8, 2021 (version 2)

Copyright

© 2021, Kikkert 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. Sanne Kikkert
  2. Dario Pfyffer
  3. Michaela Verling
  4. Patrick Freund
  5. Nicole Wenderoth
(2021)
Finger somatotopy is preserved after tetraplegia but deteriorates over time
eLife 10:e67713.
https://doi.org/10.7554/eLife.67713

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https://doi.org/10.7554/eLife.67713

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