Funding sources This work was supported by NIAMS (NIH) grant 5ARO155902-3.
CLINICAL AND LABORATORY INVESTIGATIONS
The pleasurability of scratching an itch: a psychophysical and topographical assessment
Article first published online: 4 APR 2012
© 2012 The Authors. BJD © 2012 British Association of Dermatologists
British Journal of Dermatology
Volume 166, Issue 5, pages 981–985, May 2012
How to Cite
bin Saif, G.A., Papoiu, A.D.P., Banari, L., McGlone, F., Kwatra, S.G., Chan, Y.-H. and Yosipovitch, G. (2012), The pleasurability of scratching an itch: a psychophysical and topographical assessment. British Journal of Dermatology, 166: 981–985. doi: 10.1111/j.1365-2133.2012.10826.x
Conflicts of interest None declared.
G.A.b.S. and A.D.P.P. contributed equally to this report and should be considered first authors.
- Issue published online: 23 APR 2012
- Article first published online: 4 APR 2012
- Accepted manuscript online: 13 JAN 2012 02:22PM EST
- Accepted for publication 4 January 2012
Background Scratching an itch is perceived as being pleasurable. However, an analysis of topographical variations in itch intensity, the effectiveness of scratching to provide itch relief and the associated pleasurability has not been performed at different body sites.
Objectives To examine the role of scratching pleasurability in providing itch relief by investigating whether itch intensity is perceived differently at three different sites and to assess a potential correlation between the pleasurability and itch attenuation induced by scratching.
Methods Itch was induced on the forearm, ankle and back using cowhage spicules in 18 healthy subjects. These sites were subsequently scratched by an investigator with a cytology brush immediately following itch induction. The intensity of itch with and without scratching at these sites and the pleasurability of scratching were recorded by taking visual analogue scale ratings at 30-s intervals.
Results Mean itch intensity and scratching pleasurability ratings at the ankle and back were significantly higher than on the forearm. For the forearm and ankle, the greater the itch while scratching, the higher was the pleasurability. A higher baseline itch was linked to a higher itch reduction secondary to scratching in all tested areas. Pleasurability paralleled the curve of itch reduction for the back and forearm; however, scratching pleasurability at the ankle remained elevated and only slightly decreased while itch was diminishing.
Conclusions There are topographical differences in itch intensity, the effectiveness of scratching in relieving itch and the associated pleasurability. Experimental itch induced by cowhage was more intensely perceived at the ankle, while scratching attenuated itch most effectively on the back.