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

February 21st 2025

participants’ rights

in a study approved by an institutional review board, a set of conditions relating to participants in the study and their role in the research. Participants normally should be informed about the purpose of the study (but see deception research), its procedures (i.e., what specifically is expected to occur) and the associated costs and benefits; that their data from the study will be kept confidential; whom they can contact if they have any concerns about the study; and that they can leave the study at any time without penalty. Also called subjects’ rights. See also informed consent; research ethics.