Sex Differences in Itch Perception and Modulation by Distraction – an fMRI Pilot Study in Healthy Volunteers

Background: Even though itch is a common syndrome of many diseases there is only little knowledge about sex and gender differences in pruritus, especially in central itch perception and modulation. To our knowledge, this is the first fMRI study examining sex differences in perception and its modulat...

Authors: Stumpf, Astrid
Burgmer, Markus
Schneider, Gudrun
Heuft, Gereon
Schmelz, Martin
Phan, Ngoc Quan
Ständer, Sonja
Pfleiderer, Bettina
Division/Institute:FB 05: Medizinische Fakultät
Document types:Article
Media types:Text
Publication date:2013
Date of publication on miami:18.02.2014
Modification date:24.01.2020
Edition statement:[Electronic ed.]
Source:PLoS ONE 8 (2013) 11, e79123
DDC Subject:150: Psychologie
License:CC BY 3.0
Language:English
Notes:Finanziert durch den Open-Access-Publikationsfonds 2013/2014 der Deutschen Forschungsgemeinschaft (DFG) und der Westfälischen Wilhelms-Universität Münster (WWU Münster).
Format:PDF document
URN:urn:nbn:de:hbz:6-54319551203
Permalink:http://nbn-resolving.de/urn:nbn:de:hbz:6-54319551203
Other Identifiers:DOI: 10.1371/journal.pone.0079123
Digital documents:journal.pone.0079123.pdf

Background: Even though itch is a common syndrome of many diseases there is only little knowledge about sex and gender differences in pruritus, especially in central itch perception and modulation. To our knowledge, this is the first fMRI study examining sex differences in perception and its modulation by distraction. Methods: Experimental itch was induced by application of histamine (0.1 mM) via microdialysis fibers twice at the left forearm and twice at the left lower leg in 33 healthy volunteers (17 females, 16 males). The brain activation patterns were assessed by fMRI during itch without and with distraction (Stroop task). Between the various conditions, subjects were asked to rate itch intensity, desire to scratch and pain intensity. In a second experiment in 10 of the 33 volunteers histamine was replaced by saline solution to serve as control for the ‘Stroop’ condition. Results: Women generally presented higher itch intensities compared to men during itch over the course of the experiment. A more specific analysis revealed higher itch intensities and desire to scratch in women during experimental induced itch that can be reduced by distraction at the lower legs when itch is followed by ‘Stroop’. In contrast, men depicted significant reduction of ‘itch’ by ‘Stroop’ at the forearms. Women depicted higher brain activation of structures responsible for integration of sensory, affective information and motor integration/planning during ‘itch’ and ‘Stroop’ condition when compared to men. No sex differences were seen in the saline control condition. Conclusion: Women and men exhibited localisation dependent differences in their itch perception with women presenting higher itch intensities and desire to scratch. Our findings parallel clinical observations of women reporting higher itch intensities depending on itch localisation and suffering more from itch as compared to men.