NEW YORK, NY, April 6, 2014 In a study published in the April 6 online edition of the journal Nature, a team of Columbia University Medical Center researchers led by Ellen Lumpkin, PhD, associate professor of somatosensory biology, solve an age-old mystery of touch: how cells just beneath the skin surface enable us to feel fine details and textures.
Touch is the last frontier of sensory neuroscience. The cells and molecules that initiate visionrod and cone cells and light-sensitive receptorshave been known since the early 20th century, and the senses of smell, taste, and hearing are increasingly understood. But almost nothing is known about the cells and molecules responsible for initiating our sense of touch.
This study is the first to use optogeneticsa new method that uses light as a signaling system to turn neurons on and off on demandon 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.
"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," Dr. Lumpkin said.
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 conditionsincluding diabetes and some cancer chemotherapy treatments, as well as normal agingare 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. "No one has tested whether the loss of Merkel cells causes loss of function with agingit could be a coincidencebut it's a question we're interested in pursuing," Dr. Lumpkin said.
In the future, these findings
|Contact: Karin Eskenazi|
Columbia University Medical Center