The hypothalamus is a small region of the brain. It’s located at the base of the brain, near the pituitary gland. The hypothalamus is known as the master switchboard because it's the part of the brain that controls the endocrine system and regulates the endocrine glands with the help of the pituitary gland. The hypothalamus detects the rising level of the target organ's hormones then sends either hormonal or electrical messages to the pituitary gland. In response, the pituitary gland releases hormones, which travel through the bloodstream to a target endocrine gland, instructing it to stop producing its hormones.