The hypothalamus is the section of the brain responsible for producing hormones which govern body temperature, thirst, hunger, sleep, circadian rhythm, mood, and sex drive. The effects on the circadian rhythm are the reason you can sleep well over the required sleep and still wake up tired. The depressed nerves in the hypothalamus also account for the reason our body temperature goes down when we drink. So tipping back that whisky to keep yourself warm actually does the opposite.
