Independence of brain and tympanic temperatures in an unanesthetized human.

Temperature within the brain and the esophagus and at the tympanum were obtained in a 12-yr-old male in a series of experiments that began 8 days after surgery for implantation of a drainage catheter. Fanning the face did reduce tympanic temperature but not temperature in the brain; brain temperatures followed esophageal temperatures. In long-term monitoring, temperature in the lateral ventricle was 0.5 degree C above esophageal temperature and 0.2 degree C below that in white matter 1 cm above, with the offsets fixed throughout the overnight cycle. All temperatures went through similar excursions when the face was excluded from fanning applied to the body. These observations highlight the fact that in humans the defense against hyperthermia takes advantage of cooling distributed over the entire skin surface.