Karen L. Hall
Katy E. Hoffman
George A. Gescheider
Stanley J. Bolanowski
Ronald T. Verrillo
Inst. for Sensory Res., Syracuse Univ., Syracuse, NY 13244
Thresholds were measured for the detection of vibratory stimuli in subjects ranging in age from 10 to 89 years (n=168). Vibratory stimuli of 1, 10, and 300 Hz were delivered to the thenar eminence of the right hand through a small (0.008 cm[sup 2]) and a large (2.9 cm[sup 2]) contactor. These stimuli have been shown to selectively isolate the NP I, NP II, NP III, and P channels in glabrous skin (Bolanowski et al., 1988). The results show a substantial reduction in the sensitivity of the P channel with increasing age. The NP I, NP II, and NP III channels show comparatively less reduction in sensitivity as age increases. Therefore, the P channel, which is mediated by Pacinian corpuscle (PC) fibers, shows a greater loss in sensitivity with age than the NP I, NP II, and NP III channels, which are thought to be mediated by RA, SA II, and SA I fibers, respectively. Women were found to be more sensitive than men in all but the youngest subjects. [Work supported by NIH, NIDCD.]