Comparison of child and adult vibrotactile thresholds as a function of frequency and duration

Psychophysical thresholds for the detection of sinusoidal vibration of the thenar eminence of the hand were determined for children and adults. The subjects in the child group were between 8 and 11 years old, and the adults were between 20 and 39 years old. Measurements were made for vibration frequencies ranging from 18 to 700 Hz and stimulus durations ranging from 28 to 1,000 msec. For both children and adults, thresholds were a Il-shaped function of stimulus frequency. However, the exact form of the function was influenced by the age of the subjects. At frequencies above 200 Hz, thresholds were virtually identical for children and adults, but below this frequency children were more sensitive than adults. This finding, in combination with known changes in the anatomy of the Pacinian corpuscle with age, is in agreement with a filter model of this cutaneous receptor. Furthermore, variation of stimulus duration resulted in data in agreement with the theory that two classes of mechanoreceptors, Pacinian and non-Pacinian, mediate the perception of vibration.