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melatonin

n. an amine hormone, produced mainly by the pineal gland as a metabolic product of the neurotransmitter serotonin, that helps to regulate seasonal changes in physiology and may also influence puberty. It is implicated in the initiation of sleep and in the regulation of the sleep–wake cycle. Melatonin has been investigated in clinical studies as a hypnotic and for the management of circadian rhythm sleep disorders. Although these studies are as yet inconclusive, melatonin is widely available as an over-the-counter medication.

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Psychology term of the day

December 18th 2024

sport

sport

n.

1. a physical contest between individuals or teams that is conducted under codified rules, is controlled by nonparticipants, and can have only one winner.

2. in genetics, an organism that has undergone mutation and is distinctly different from its parents.