Mystery of touch revealed

Researchers have managed to discover how cells just beneath the skin surface enable us to feel fine details and textures.

This study is the first to use optogenetics-a new method that uses light as a signaling system to turn neurons on and off on demand-on skin cells to determine how they function and communicate.

The team showed that skin cells called Merkel cells can sense touch and that they work virtually hand in glove with the skin's neurons to create what we perceive as fine details and textures.

Ellen Lumpkin, PhD, associate professor of somatosensory biology, said that these experiments are the first direct proof that Merkel cells can encode touch into neural signals that transmit information to the brain about the objects in the world around us.

The findings not only describe a key advance in our understanding of touch sensation, but may stimulate research into loss of sensitive-touch perception.

Several conditions-including diabetes and some cancer chemotherapy treatments, as well as normal aging-are known to reduce sensitive touch. Merkel cells begin to disappear in one's early 20s, at the same time that tactile acuity starts to decline.

The study has been published online in the journal Nature.