Epiphysis Cerebri, also known as the pineal gland, is a small endocrine gland found in the brain. It is responsible for producing and secreting the hormone melatonin, which regulates sleep patterns and circadian rhythms. Synonyms for Epiphysis Cerebri include pineal body, pineal organ, and pineal glandula. This gland plays a vital role in physiological functions and is also associated with spiritual and transcendent experiences. Some also refer to it as the "third eye" due to its location and potential connection to intuition and mystical experiences. The pineal gland is an important part of the human body and its functions have been studied extensively for centuries.