Point: humans do demonstrate selective brain cooling during hyperthermia.

Selective brain cooling (SBC) is defined by the International Union of Physiological Sciences (11) as “a lowering of the brain temperature either locally or as a whole below arterial blood temperature.” Since the first observations of SBC in hyperthermic, nonhuman mammals (1, 14, 25), there have been efforts to resolve the physiological mechanisms underlying this response (3, 12, 19, 27). It is still hotly debated whether SBC also exists in hyperthermic humans. This contribution is first to give evidence confirming SBC exists in humans, second to outline the mechanisms underlying SBC, third to counter arguments suggesting that SBC is absent in humans, and finally to present a physiological rationale for human SBC.