The skin is a human being’s largest sensory organ, helping to distinguish between a pleasant contact, like a caress, and a negative sensation, like a pinch or a burn. Previous studies have shown that these sensations are carried to the brain by different types of sensory neurons that have nerve endings in the skin. Only a few of those neuron types have been identified, however, and most of those detect painful stimuli. Now biologists at the California Institute of Technology (Caltech) have identified in mice a specific class of skin sensory neurons that reacts to an apparently pleasurable stimulus.
More specifically, the team, led by David J. Anderson, Seymour Benzer Professor of Biology at Caltech, was able to pinpoint individual neurons that were activated by massage-like stroking of the skin. The team’s results are outlined in the January 31 issue of the journal Nature.

