Spinal signaling of C-fiber mediated pleasant touch in humans

  1. Andrew G Marshall  Is a corresponding author
  2. Manohar L Sharma
  3. Kate Marley
  4. Hakan Olausson
  5. Francis P McGlone
  1. University of Liverpool, United Kingdom
  2. Walton Centre NHS Foundation Trust, United Kingdom
  3. University Hospital Aintree, United Kingdom
  4. Linköping University, Sweden
  5. Liverpool John Moores University, United Kingdom

Abstract

C-tactile afferents form a distinct channel that encodes pleasant tactile stimulation. Prevailing views indicate they project, as with other unmyelinated afferents, in lamina I-spinothalamic pathways. However, we found that spinothalamic ablation in humans, whilst profoundly impairing pain, temperature and itch, had no effect on pleasant touch perception. Only discriminative touch deficits were seen. These findings preclude privileged C-tactile-lamina I-spinothalamic projections and imply integrated hedonic and discriminative spinal processing from the body.

Data availability

All data generated or analysed during this study are either included in the manuscript and supporting files or Open Science Framework - accession code g8vyk

The following data sets were generated

Article and author information

Author details

  1. Andrew G Marshall

    Institute of Aging and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
    For correspondence
    andrew.marshall@liverpool.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8273-7089
  2. Manohar L Sharma

    Department of Pain Medicine, Walton Centre NHS Foundation Trust, Liverpool, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Kate Marley

    Specialist Palliative Care Team, University Hospital Aintree, Liverpool, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Hakan Olausson

    Center for Social and Affective Neuroscience, Linköping University, Linköping, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  5. Francis P McGlone

    School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

Funding

Pain Relief Foundation

  • Andrew G Marshall

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

Ethics

Human subjects: Ethical approval was obtained through the Health Research Authority National Research Ethics Service (Preston NRES committee, study reference 14/NW/1247). The study was conducted in accordance with the Declaration of Helsinki. Written informed consent was taken from all study participants.

Copyright

© 2019, Marshall 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. Andrew G Marshall
  2. Manohar L Sharma
  3. Kate Marley
  4. Hakan Olausson
  5. Francis P McGlone
(2019)
Spinal signaling of C-fiber mediated pleasant touch in humans
eLife 8:e51642.
https://doi.org/10.7554/eLife.51642

Share this article

https://doi.org/10.7554/eLife.51642

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