Widespread nociceptive maps in the human neonatal somatosensory cortex
- University College London, United Kingdom
- University College London Hospitals NHS Foundation Trust, United Kingdom
Abstract
Topographic cortical maps are essential for spatial localisation of sensory stimulation and generation of appropriate task-related motor responses. Somatosensation and nociception are finely mapped and aligned in the adult somatosensory (S1) cortex, but in infancy, when pain behaviour is disorganised and poorly directed, nociceptive maps may be less refined. We compared the topographic pattern of S1 activation following noxious (clinically required heel lance) and innocuous (touch) mechanical stimulation of the same skin region in newborn infants (n=32) using multi-optode functional near-infrared spectroscopy (fNIRS). Within S1 cortex, touch and lance of the heel elicit localised, partially overlapping increases in oxygenated haemoglobin concentration (D[HbO]), but while touch activation was restricted to the heel area, lance activation extended into cortical hand regions. The data reveals a widespread cortical nociceptive map in infant S1, consistent with their poorly directed pain behaviour.
Data availability
All raw data files are open access and are available to download from Figshare (https://doi.org/10.6084/m9.figshare.13252388.v2).
Article and author information
Author details
Madeleine Verriotis
Funding
Medical Research Council (MR/M006468/1)
- Judith Meek
- Lorenzo Fabrizi
- Maria Fitzgerald
Medical Research Council (MR/L019248/1)
- Lorenzo Fabrizi
Engineering and Physical Sciences Research Council (EP/N025946/1)
- Robert J Cooper
Medical Research Council (MR/S003207/1)
- Judith Meek
- Lorenzo Fabrizi
- Maria Fitzgerald
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 for this study was given by the NHS Health Research Authority (London - Surrey Borders) and the study conformed to the standards set by the Declaration of Helsinki. Informed written parental consent was obtained before each study (REC no: 11/LO/0350; NIHR Portfolio Study ID: 12036). Separate media consent was obtained from the parent to use a photo of their child in academic publications (Figure 4a).
Copyright
© 2022, Jones 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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Widespread nociceptive maps in the human neonatal somatosensory cortex
eLife 11:e71655.
https://doi.org/10.7554/eLife.71655
Further reading
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