Epithalamus

**Semantic type:** Body Part, Organ, or Organ Component

**Definition:** A dorsal posterior section of the diencephalon that comprises the trigonum habenula, habenular commissure, stria medullaris, and pineal gland. The epithalamus is the connection between the limbic system and basal ganglia, and is involved in the secretion of melatonin and the regulation of motor pathways and emotions.