Abstract
A device to measure two-point-discrimination and gap-discrimination thresholds is described. The apparatus is capable of controlled and reliable delivery of forces up to 42.50 g while determining point of skin contact and subsequent depth of skin indentation during threshold determination. Stimulus delivery is controlled by computer software that deactivates a solenoid, allowing a counterbalanced beam with one of two stimulus wheels mounted on its end to rise and stimulate the skin. Depth of skin indentation is recorded by hardware that monitors the output of a photocell reflecting the position of the beam. The apparatus allows complete computer control of all data acquisition and recording.
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This research was supported in part by the National Institute on Aging of the National Institutes of Health (Grant AG02085). Special thanks to Keith S. Wood for his programming expertise and tenacity.
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Woodward, K.L., Kenshalo, D.R. & Oliff, G.K. A tactile stimulation device for measuring two-point and gap discrimination thresholds in humans. Behavior Research Methods, Instruments, & Computers 22, 440–442 (1990). https://doi.org/10.3758/BF03203191
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DOI: https://doi.org/10.3758/BF03203191