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.
It is the hormone produced by the pineal gland that also acts as a neurotransmitter. It basically controls the sleep-wake cycle. It is also associated with controlling mood and sexual behavior. The production of melatonin is dependent on light.t is the hormone produced by the pineal gland that also acts as a neurotransmitter. It basically controls the sleep-wake cycle. It is also associated with controlling mood and sexual behavior. The production of melatonin is dependent on light.