Massage therapists spend much of their workday touching, with their palpation, effleurage, petrissage and tapotement.
Now, researchers have found that the timing and frequency of vibrations produced in the skin when you run your hands along a surface plays an important role in how we use our sense of touch to gather information about the objects and surfaces around us.
The sense of touch has traditionally been thought of in spatial terms; in other words, receptors in the skin are spread out across a grid of sorts, and when you touch something this grid of receptors transmits information about the surface to your brain.
In their new study, Sliman Bensmaia, Ph.D., assistant professor of organismal biology and anatomy at the University of Chicago, and his team found that the skin is also highly sensitive to vibrations, and that these vibrations produce corresponding oscillations in the afferents, or nerves, that carry information from the receptors to the brain.
The precise timing and frequency of these neural responses convey specific messages about texture to the brain, much like the frequency of vibrations on the eardrum conveys information about sound.
“We’re trying to build a theory of what makes things feel the way they feel,” Bensmaia said. “This is the beginning of a story that’s really going to change the way people think about the somatosensory system.”