The pituitary gland is a pea-sized organ found at the base of the brain, level with the eyes in the middle of the head. Known as the “master gland,” it produces and helps balance many hormones that help direct processes or stimulate other glands to produce hormones. Together with the hypothalamus, the pituitary gland regulates the autonomic nervous system. It is made up of four subparts: the neurohypophysis (posterior pituitary), adenohypophysis (anterior pituitary), intermediate pituitary (pars intermedia), and pituitary stalk.