Abstract: A subject's forehead, and underlying pre-frontal cortex may be cooled by positioning a pre-cooled heat transfer pack on the subject's forehead so that the heat transfer pack is in thermal communication with the subject's forehead, the temperature of the pre-cooled heat transfer pack being below 10° Celsius. Thermal communication between the subject's forehead and the heat transfer pack may be maintained for a period of time sufficient to cool the subject's pre-frontal cortex. Cooling of the pre-frontal cortex may slow the metabolic rate of the subject's pre-frontal cortex and/or induce an onset of sleep for the subject.

Abstract: A heat transfer system may include a heat transfer machine adapted to thermally couple to an heat transfer pack housed within an heat transfer device and transfer heat from the heat transfer pack using a power supply. The heat transfer device may include a housing and a heat transfer pack. The heat transfer pack may be adapted to thermally couple to the heat transfer machine, transfer heat to the heat transfer machine while thermally coupled to the heat transfer machine, and transfer heat from a mammal's skin when the heat transfer device is in contact with the mammal's skin and uncoupled from the heat transfer machine.