A pearl-sized region in the human brain, the hypothalamus is the brain’s control center for energy balance. The hypothalamus regulates body temperature, thirst, hunger, fatigue, sleep, circadian cycles, hormone production, and sexual behavior. The hypothalamus is the central clearinghouse for many functions connected to the autonomic nervous system.
The hypothalamus links the rest of the body intelligence system to the endocrine system via the pituitary gland. A complex interchange of crosstalk within the hypothalamus results in decisions that give the pituitary gland its marching orders.