
Unmyelinated tactile afferents signal touch and project to insular cortex
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ABSTRACT There is dual tactile innervation of the human hairy skin: in addition to fast-conducting myelinated afferent fibers, there is a system of slow-conducting unmyelinated (C) afferents
that respond to light touch. In a unique patient lacking large myelinated afferents, we found that activation of C tactile (CT) afferents produced a faint sensation of pleasant touch.
Functional magnetic resonance imaging (fMRI) analysis during CT stimulation showed activation of the insular region, but not of somatosensory areas S1 and S2. These findings identify CT as a
system for limbic touch that may underlie emotional, hormonal and affiliative responses to caress-like, skin-to-skin contact between individuals. Access through your institution Buy or
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THE MECHANOSENSORY NEURONS OF TOUCH AND THEIR MECHANISMS OF ACTIVATION Article 26 July 2021 CORTICAL RESPONSES TO TOUCH REFLECT SUBCORTICAL INTEGRATION OF LTMR SIGNALS Article 17 November
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Scholar Download references ACKNOWLEDGEMENTS This study was supported by the Canadian and Swedish Medical Research Councils (grants 3546, 12170 and 3548), and the Ingabritt and Arne
Lundberg Research Foundation. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Clinical Neurophysiology, Sahlgrenska University Hospital, Göteborg, S-413 45, Sweden H. Olausson,
H. Backlund & B.G. Wallin * Department of Physiology, University of Montreal, Montreal, H3C 3J7, Quebec, Canada Y. Lamarre * Department of Physiology, Göteborg University, Göteborg,
S-413 45, Sweden H. Backlund & Å.B. Vallbo * Department of Anesthesia, McGill University, Montreal, H3G IY6, Quebec, Canada C. Morin, I. Strigo & M.C. Bushnell * Department of
Radiation Physics, Sahlgrenska University Hospital, Göteborg, S-413 45, Sweden G. Starck * Department of Radiology, Sahlgrenska University Hospital, Göteborg, S-413 45, Sweden S. Ekholm *
Department of Mathematics and Statistics, McGill University, Montreal, H3G IY6, Quebec, Canada K. Worsley Authors * H. Olausson View author publications You can also search for this author
inPubMed Google Scholar * Y. Lamarre View author publications You can also search for this author inPubMed Google Scholar * H. Backlund View author publications You can also search for this
author inPubMed Google Scholar * C. Morin View author publications You can also search for this author inPubMed Google Scholar * B.G. Wallin View author publications You can also search for
this author inPubMed Google Scholar * G. Starck View author publications You can also search for this author inPubMed Google Scholar * S. Ekholm View author publications You can also search
for this author inPubMed Google Scholar * I. Strigo View author publications You can also search for this author inPubMed Google Scholar * K. Worsley View author publications You can also
search for this author inPubMed Google Scholar * Å.B. Vallbo View author publications You can also search for this author inPubMed Google Scholar * M.C. Bushnell View author publications You
can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to H. Olausson. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing
financial interests. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Olausson, H., Lamarre, Y., Backlund, H. _et al._ Unmyelinated tactile afferents
signal touch and project to insular cortex. _Nat Neurosci_ 5, 900–904 (2002). https://doi.org/10.1038/nn896 Download citation * Received: 04 April 2002 * Accepted: 08 July 2002 * Published:
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