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This test is used to study certain sleep disorders and other dysfunctions of our biological clock.

Melatonin is produced by the pineal gland, a small gland located in the brain. It helps control hormone secretion cycles like the menstrual cycle and circadian rhythm (the body’s biological clock that regulates the sleep-wake cycles). When there is less light, melatonin levels increase, and when there is more light, they drop. Situations involving, for example, the use of powerful lighting in the evening, the absence of light during winter, certain cancers, and other dysfunctions of the central nervous system can also influence melatonin secretion and activity, thus undermining the quality of sleep (insomnias) and wakefulness. Examples of possible manifestations include excessive daytime sleepiness, poor results in the treatment of sleep apnea despite the use of a CPAP machine, and physical, neurocognitive or emotional disorders, among others.

Term of the Week

Hot zone

A hot zone is a section of a facility (sometimes an entire facility or even a city district) where there is a high risk of contamination by patients with an infectious disease. All individuals entering a hot zone must respect appropriate protective measures. By analogy, “cold zone” and “warm zone” are used to refer to areas where there is no infected individual or only individuals suspected of having an infection.