Development of vibrotactile measurement techniques for assessing mechanoreceptor performance at the fingertip

In recent years knowledge of the basic physiology of mechanoreceptors has advanced considerably. The translation of this knowledge into psychophysical threshold measurement techniques for assessing mechanoreceptor performance at the fingertip will be described. The sensitivity of three types of mechanoreceptors, the Pacinian corpuscles, Meissner corpuscles, and Merkel disks, is obtained from threshold measurements with sinusoidal vibratory stimuli at various frequencies across the band from 2–400 Hz. Parameters affecting the coupling of the vibrating probe to the finger, namely, static force, skin indentation, and probe diameter, have a significant and different effect on the thresholds for the different receptors. The role of background vibration of physiological origin (physiological noise) on the perception thresholds will be discussed.