The relationship between skin compliance, age, gender, and tactile discriminative thresholds in humans

Earlier research has suggested that tactile sensitivity, like visual and auditory acuity, may decrease with increasing age. But are decrements in tactile sensitivity attributable to changes in the nervous system, or simply to alterations in the mechanical properties of the skin? In the present study, skin compliance and discriminative thresholds for two-point and gap stimuli were measured on the pad of the left index finger of 102 persons ranging in age from 18 to 84 years. For both types of stimuli, age was found to be a significant predictor of tactile sensitivity, even when skin compliance and gender were controlled. The relationship between increasing age and decrements in tactile discrimination is apparently not attributable to changes in the mechanical properties of the skin, but to other factors, which may include changes in the nervous system affecting the speed, quantity, or quality of information processing.