A note on warm and cold spots

Abstract

An investigation of cutaneous sensation in 10 healthy adults was made with the following results: (1) A cold stimulus applied to a warm spot never gave a sensation of warmth and vice versa; (2) Painful stimulation never gave a thermal sensation; (3) All thermal stimuli and all mechanical stimuli gave a sensation of touch or pressure; and (4) A thermally neutral mechanical stimulus applied to warm spots sometimes, but not consistently, gave a sensation of warmth. Results did not coincide with past statements of other investigators that warm and cold spots are insensitive to mechanical and painful stimulation or that cold spots give a sensation of cold when painfully or mechanically stimulated. It is concluded that the hypothesis stating that each of 4 basic modalities of sensation are subserved by a morphologic structure with its own set of nerve fibers, stimulation of which can cause only that modality of sensation subserved cannot be substantiated.