What is a 'Z-Score'. A Z-score is a numerical measurement of a value's relationship to the mean in a group of values. If a Z-score is 0, it represents the score is identical to the mean score. Z-scores may also be positive or negative, with a positive value indicating the score is above the mean and a negative score indicating it is below the mean.
The pineal gland, also known as the pineal body, is an important endocrine gland that produces the hormone melatonin. Melatonin plays a key role in the sleep/wake cycle and the bodyâs response to sunlight. The pineal gland is a small, pinecone-shaped mass of glandular tissue about 1/3 of an inch (8 mm) long.
Melatonin and serotonin are two naturally occurring substances found in your body. Your pineal gland produces melatonin, and your intestinal cells and brainâs nervous center produces serotonin. Both melatonin and serotonin play several roles in human behavior and cognition. Serotonin syndrome is a medical condition defined as excess levels of serotonin in your body.