BODY TEMPERATURE OF NAIVE MALE SPRAGUE-DAWLEY RATS WAS RECORDED CONTINUOUSLY IN 2 ACTIVITY DEVICES UNDER AD LIB AND FOOD OR WATER DEPRIVATION CONDITIONS. BOTH HUNGER AND THIRST LOWERED SUBDERMAL TEMPERATURE AND INCREASED WHEEL RUNNING, BUT ONLY FOOD DEPRIVATION INCREASED STABILIMETER ACTIVITY. WHEEL RUNNING PRODUCED CONSIDERABLE TEMPERATURE ELEVATION UNDER ALL CONDITIONS WHILE STABILIMETER ACTIVITY PRODUCED ONLY SLIGHT AND IRREGULAR TEMPERATURE INCREMENTS. THE EFFECTS OF HUNGER AND THIRST ON THERMOREGULATORY BEHAVIOR WERE EXAMINED IN A DEVICE WHICH PERMITTED SS TO RAISE THEIR BODY TEMPERATURE WITHOUT RESORTING TO INSTRUMENTAL OR LOCOMOTOR ACTIVITY. BOTH HUNGER AND THIRST HAVE A PRONOUNCED EFFECT ON BODY TEMPERATURE, BUT DEPRIVATION-INDUCED CHANGES IN RUNNING WHEEL AND STABILIMETER ACTIVITY CANNOT BE VIEWED AS SURROGATE THERMOREGULATORY BEHAVIORS. (PsycINFO Database Record (c) 2006 APA, all rights reserved)