Sudomotor Activity as Affected by the Thermal Status of the Skin in a Warm Environment ∗

Summary

With experiments conducted in a warm environment it has been shown that the temperature of the skin exerts a consistent influence on the sweating activity in man. Skin temperature, both below and above 33° acts locally on the sweat glands. In addition, it also acts through the reflex neural pathways. The local effect could be demonstrated even when the driving force of the internal temperature was in the opposite direction. The peripheral influence of skin temperature on sweat glands was present when the glands were stimulated by carbon dioxide inhalation. The local effect of skin temperature did not appear to involve any reflex arc; nor could it be ascribed to changes in physical phenomena like diffusion and aqueous vapor tension on the skin surface. The interaction of intracranial and cutaneous temperatures on sudomotor activity appeared to be multiplicative in nature.