Hypothalamus

The body’s master gland located below the thalamus regulating hormonal and internal regulation of bodily functions as directed by the brain. See also hypothalamus, pituitary, and adrenal gland axis (HPA).

Reference:

Bear, M.F., Connors, B.W. & Paradiso, M.A. (2001). Neuroscience: Exploring the Brain. (2nd Edition). Baltimore, MD: Lippincott Williams & Wilkins.