Some Must Watch While Some Must Sleep is about the mystery of sleep. It tells in nontechnical language how scientists are intensively searching and what they have learned about a complex state that rivals waking consciousness in importance. There is encouraging progress towards answers to the great puzzles: Do we really need to sleep? How much sleep do we need? Why do we sleep? Why do we dream? Immensely readable and often humorous, this book is an incisive personal report to the reader from one of the world's leading sleep researchers. The topics include the history of the research, the characteristics of dreaming and non-dreaming sleep, the effects of sleep and dream deprivation, and the relation of sleep and dreams to drugs, hypnosis, ESP, mental illness, circadian rhythms, and "brainwashing." Dr. Dement also discusses what is known about sleep disturbances such as narcolepsy, sleep apnea, and insomnia.--Back cover.