Spinal signaling of C-fiber mediated pleasant touch in humans
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
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Marshall_September_2019_Cordotomy_Database_PsychophysicsOpen Science Framework, g8vyk.
Article and author information
Author details
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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