ABSTRACT
The brain is the most temperature sensitive organ in the body. The primary function of the body's thermal regulation system is to assure the brain and other vital organs of a constant temperature under any circumstances, within the capabilities of the system. The temperature of the body is almost entirely regulated by the autonomic nervous system from centers located in the hypothalamus, which is situated directly beneath the cerebral cortex. Anesthesiologists routinely suppress the activity of the hypothalamus when they wish to induce hypothermia during surgery. As in any regulated system, thermal control is based on a feedback mechanism which must include a reference (a substance needed to determine the "set point"), temperature sensors (warm and cold receptors located in the skin),37 communication lines (nerve fibers that pass signals beetween the different parts of the system), actuators (the organs capable of generating or losing heat: muscles, skin, lungs, etc.), and a "control module" (hypothalamus).
