Pineal Gland
The pineal gland, also known as the pineal body, conarium, or epiphysis cerebri, is a small endocrine gland located in the epithalamus, near the center of the brain, between the two hemispheres. It produces melatonin, a serotonin-derived hormone that modulates sleep patterns in both circadian and seasonal cycles.0 The main function of the pineal gland is to receive information about the state of the light-dark cycle from the environment and convey this information by the production and secretion of melatonin.2 The pineal gland contains high levels of calcium and can be used by radiographers to mark the middle of the brain in X-ray images.1