Om at vibrasjon på huden kan gjøre at C-fibre ikke reagerer så kraftig. Kan indikere en smertereduksjon.
Vibrostimulation of skin from the crus of the cat at frequencies of 10, 30, and 50/sec evokes a response of mechanoreceptors innervating group Aβ and Aδ fibers to the presentation of each vibrostimulus. The higher the frequency of vibrostimulation, the more clearly manifest are changes in on- and off-responses on a neurogram recorded from the n. saphenus branch. These changes are a result of a decrease in the number of impulses evoked by each vibratory beat. Mechanoreceptors innervated by fibers of group C are not excited as a result of vibrostimulation at these frequencies. After preliminary vibrostimulation, a portion of the mechanoreceptors innervated by C-fibers do not respond to presentation of a mechanical test stimulus (stretching of the skin); the higher the frequency of vibrostimulation, the smaller is the number of reacting receptors.