Background of the study: Thermo-regulation is an important aspect of human homeostasis. A decrease in brain and/or body temperature will increase energy requirements and eventually food intake, which acts as a defence against hypothermia. The hypothalamus plays a central role in the regulation of temperature as well as in the control of energy intake, feeding behaviour and lipid and glucose metabolism. The effect of both cooling and changes in energy demand, will therefore be reflected in hypothalamic activity.