The human body clock and how it controls melatonin release

Circadian rhythm desynchronization can occur due to factors like shift work, aging, and certain psychiatric conditions.

• The internal biological clock is located in the suprachiasmatic nuclei of the anterior hypothalamus.
• Clock genes and environmental factors help synchronize this clock to a 24-hour cycle.
• Disruptions to the circadian system can lead to misalignment with astronomical time.
• The circadian system includes the clock, the retinohypothalamic tract, and melatonin from the pineal gland.
• Light and melatonin have phase response curves that may aid in treating sleep circadian disorders.

Simplified