Sleep Cycles: One rapid eye movement (REM) stage and three non-REM stages that altogether last about 90 to 120 minutes Benefits: Physical and mental recuperation and memory consolidation Disorders: ...

“Sorrow can be alleviated by good sleep, a bath, and a glass of wine.” —Thomas Aquinas Getting enough restful sleep is not a basic luxury, it is a biologic necessity. Sleep is far more than about ...

Narcolepsy is caused by a deficiency of orexin, a brain chemical that regulates wakefulness and REM sleep. The MSLT and polysomnography are gold standards for diagnosing narcolepsy. Medications like ...

When a person is asleep, their core body temperature drops. Heart rate and breathing also slow down and overall metabolic activity decreases by about 10%. A sleeping body may seem inactive at first ...