Seeing an itch-related image, such as a person scratching or a picture of ants on skin, can trigger a scratch response, researchers from the University of Manchester have found.
Their study tested if pictures could generate feelings of itch in healthy volunteers. A group of 30 volunteers were shown images related to itching, such as skin conditions, ants crawling on skin, or fleas, or neutral images, such as butterflies.
They were asked to rate how itchy they felt with a score out of 10. Researchers also recorded the number of times participants scratched during the task.
Participants reported greater itch sensations when viewing images related to scratching than neutral ones, and rated images with skin contact higher than those of a skin condition.
Similarly, the amount of scratching was also higher in itch-related pictures. The authors suggest the study may provide behavioural evidence linking contagious itch to the mirror neuron system in the brain.
Lloyd DM, Hall E, Hall S et al. Br J Dermatol 2013; 168: 106-11.