Length discrimination on the skin.
D001132:Arm / Q000502:physiology; D004056:Differential Threshold; D004192:Discrimination, Psychological; D004215:Distance Perception; D005260:Female; D006801:Humans; D007600:Judgment; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D010812:Physical Stimulation; D011601:Psychophysics; D012858:Size Perception; D012879:Skin Physiological Phenomena; D014110:Touch