Home > Encyclopedia of Children's Health > Narcolepsy

Definition

Narcolepsy is a disorder of the nervous system marked by excessive daytime sleepiness, uncontrollable sleep attacks, and cataplexy (a sudden loss of muscle tone, usually lasting up to half an hour). The American Psychiatric Association (APA) classifies narcolepsy as a sleep disorder in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders, or DSM-IV. The National Institute of Neurological Disorders and Stroke (NINDS) defines narcolepsy as a "disorder caused by the brain's inability to regulate sleep-wake cycles normally." The disorder is sometimes called Gélineau's syndrome because it was first identified in 1880 by the French neurologist Jean-Baptiste Gélineau. The word narcolepsy itself comes from two Greek words that together mean...