SCRATCHING PATTERNS .1. INFLUENCE OF SITE

[摘要] Observations were made on the length of scratch strokes in response to itching at various sites. It was found they are progressively shorter toward the periphery of the limbs and longer centripetally. They are longer, too, on the trunk, but shorter on the head with very definite gradients, as from the ear to the mouth. The length of the scratch at any area can be correlated inversely with its density of tactile end organs and intensity of touch-sense, coinciding with its ability to localize a tactile stimulus. It appears that a relatively similar number of tactile endings must be stimulated to suppress itching, regardless of its site; but important, too, is the twin factor of distinctive quality of touch-sense inherent at each area of the skin.