Effects of skin temperature and body site on psychophysical characteristics of cutaneous mechanoreceptor subsystems Free

Psychophysical detection thresholds were obtained at the thenar eminence and volar forearm using 16 sinusoidal frequencies between 15 and 700 Hz. A small (0.008 cm²) contactor was used, which preferentially excites non‐Pacinian (NP) subsystems. Measurements were made using carefully controlled (± 0.5 °C) skin surface temperatures of 15°, 20°, 25°, 30°, 35°, and 40 °C to enhance or degrade the subsystem responses. The results show several frequency characteristics that cannot be ascribed to activity in the Pacinian system, but do conform to electrophysiological measurements of Ruffini capsules, Meissner corpuscles, and Merkel cells. When threshold values are averaged across temperatures, the resultant curve is approximately flat. The results suggest that the NP system is probably composed of more than a single receptor type and that well‐controlled skin temperature is necessary for the precise measurement of vibrotactile sensation.