A dorsal posterior segment of the diencephalon incorporating the habenula (a strap-like connection from the pineal gland to the diencephalon adjacent to posterior end of the roof of the third ventricle), the stria medullar is (a connection from the anterior region of the thalamus and the pineal body), and the pineal body, which connects the limbic system to other regions of the brain. It functions in the regulation of hunger and thirst (habenula) and in the secretion of melatonin (pineal gland), also known as the ‘Dracula hormone’ as it is only secreted at night, and functions as a sleep inducer as well as in sexual development.
See Diencephalon, Limbic system, Pineal gland, Thalamus, Ventricle