Comparison of Brain Functional Response to Mechanical Prickling Stimuli to the Glabrous and Hairy Skin

The study examined brain responses to mechanical prickling stimuli on glabrous (fingertip) and hairy (forearm) skin in eight healthy male subjects using fMRI. It found that hairy skin stimulation evoked a stronger prickle sensation involving both pain and itch, with activation of the precuneus and more emotional processing. In contrast, glabrous skin stimulation primarily activated regions related to tactile information without involving itch. The differences in brain activation are attributed to the varying types and numbers of receptors in each skin type, with glabrous skin providing more sensory information and hairy skin more emotional information. These findings highlight the distinct cognitive processing of prickle sensations between different skin types.