Hypothalamus

hypothalamus, region of the brain lying below the thalamus and making up the floor of the third cerebral ventricle. The hypothalamus is an integral part of the brain. It is a small cone-shaped structure that projects downward from the brain, ending in the pituitary (infundibular) stalk, a tubular connection to the pituitary gland. The hypothalamus contains a control centre for many functions of the autonomic nervous system, and it has effects on the endocrine system because of its complex interaction with the pituitary gland.