Neural basis of contagious itch and why some people are more prone to it

Holle, Henning; Warne, Kimberley; Seth, Anil K.; Critchley, Hugo D.; Ward, Jamie

Abstract

Watching someone scratch himself can induce feelings of itchiness in the perceiver. This provides a unique opportunity to characterize the neural basis of subjective experiences of itch, independent of changes in peripheral inputs. In this study, we first established that the social contagion of itch is essentially a normative response (experienced by most people), and that the degree of contagion is related to trait differences in neuroticism (i.e., the tendency to experience negative emotions), but not to empathy. Watching video clips of someone scratching (relative to control videos of tapping) activated, as indicated by functional neuroimaging, many of the neural regions linked to the physical perception of itch, including anterior insular, primary somatosensory, and prefrontal (BA44) and premotor cortices. Moreover, activity in the left BA44, BA6, and primary somatosensory cortex was correlated with subjective ratings of itchiness, and the responsivity of the left BA44 reflected individual differences in neuroticism. Our findings highlight the central neural generation of the subjective experience of somatosensory perception in the absence of somatosensory stimulation. We speculate that the habitual activation of this central "itch matrix" may give rise to psychogenic itch disorders.

Citation

Holle, H., Warne, K., Seth, A. K., Critchley, H. D., & Ward, J. (2012). Neural basis of contagious itch and why some people are more prone to it. Proceedings of the National Academy of Sciences of the United States of America, 109(48), 19816-19821. https://doi.org/10.1073/pnas.1216160109

• Journal Article Type: Article
• Acceptance Date: Oct 12, 2012
• Online Publication Date: Nov 12, 2012
• Publication Date: Nov 27, 2012
• Deposit Date: Nov 13, 2014
• Journal: Proceedings of the National Academy of Sciences of the United States of America
• Print ISSN: 0027-8424
• Publisher: National Academy of Sciences
• Peer Reviewed: Peer Reviewed
• Volume: 109
• Issue: 48
• Pages: 19816-19821
• DOI: https://doi.org/10.1073/pnas.1216160109
• Keywords: Multidisciplinary
• Public URL: https://hull-repository.worktribe.com/output/468520
• Contract Date: Nov 13, 2014