MEDICAL PHYSIOLOGY

Detailed explanation-1: -The hormone melatonin plays a role in the sleep-wake cycle. Natural levels of melatonin in the blood are highest at night. Some research suggests that melatonin supplements might be helpful in treating sleep disorders, such as delayed sleep phase. They also may provide some relief from insomnia and jet lag.

Detailed explanation-2: -Your central circadian clock, located in your brain, tells you when it is time for sleep. Other circadian clocks are in organs throughout your body. Your body’s internal clocks are in sync with certain cues in the environment. Light, darkness, and other cues help determine when you feel awake and when you feel drowsy.