Why do we sleep? How much sleep do we really need? What causes sleep apnea, narcolepsy, and insomnia-and what can be done about these sleep disorders? Why do older people have more trouble sleeping than young people? We have all puzzled over-or been plagued by-the mysteries of sleep. Now a leading researcher on sleep provides an engaging and informative introduction to the subject that answers many of our questions. Peretz Lavie surveys the entire field of sleep research and sleep medicine-from the structure of sleep stages and the brain centers involved in sleep regulation to the reasons for and significance of dreams, the importance of sleep in maintaining good health, and the function of biological rhythms-interweaving facts with fascinating case histories, anecdotes, and personal reflections. We learn, for example, about: ⁊development of sleep patterns from infancy to adulthood and in the aged; ⁊the wide variety of sleep habits in animals; ⁊dreams of Holocaust survivors; ⁊sleep under the threat of Scud missile attacks; ⁊how melatonin influences sleep; ⁊the story of the "Acrobat's Leap" sleep-deprivation experiments in the Israeli army; ⁊how to treat insomnia; ⁊what to do with a baby who refuses to go to sleep; and much more. Originally published in Hebrew to great acclaim, this book will enlighten and entertain everyone interested in how and why we sleep.