An Automated Tactile Tester for evaluation of cutaneous sensibility

The Automated Tactile Tester (ATT) is a computer-controlled device designed to measure patients' cutaneous perception of touch, vibration, temperature, and pain. The ATT provides repeatable and precise control of the amplitude, rate of application, and duration of stimuli. Threshold values for skin indentation (touch), high- and low-frequency vibration, pinprick (sharpness), warmth, and two-point discrimination were obtained with the ATT from the fingers of 62 normal subjects. Manual monofilament and two-point discrimination tests were also performed on the same subjects. All the tests with the ATT, except pinprick, showed a statistically significant increase in threshold with age. There were no significant differences attributable to the hand or digit tested or the sex of the subject. These data were used to derive age-adjusted criteria for normal sensory function in the glabrous skin of the fingers. Thresholds were found to remain within normal limits when these subjects were retested at various time intervals. We conclude that the ATT provides repeatable and reliable measurements of sensory function in the skin and has potential application in the diagnosis and evaluation of compression and other peripheral neuropathies.