by Matthew Cobb
Everyone knows that kittehs love being stroked. Indeed it’s something that is common to many mammals. But why and how? A paper in Nature by Sophia Vrontou and co-workers addresses the “how” question – that is, what are the underlying mechanisms – looking at mice. The opening sentences are limpid:
Stroking of the skin produces pleasant sensations that can occur during social interactions with conspecifics, such as grooming:. Despite numerous physiological studies, molecularly defined sensory neurons that detect pleasant stroking of hairy skin in vivo have not been reported.
They identified a particular set of sensory neurons that innervate hairy skin in mice and are activated by stroking, not pinching, and were able to show that this stimulation is apparently rewarding for the mice.
I won’t go into it any more, because Nature has made an excellent LOLcat video which explains everything about the mechanism [MAKE SURE YOU WATCH IT RIGHT TO THE END]. The issue now is to try to understand where and when this sense evolved in the mammalian lineage.
The article even made the cover!
Sophia Vrontou, Allan M. Wong, Kristofer K.Rau, H.Richard Koerber & David J. Anderson (2013) Genetic identification of C fibres that detect massage-like stroking of hairy skin in vivo. Nature 493:669–673
h/t My ex-PhD student @marvel_matt