viii, 360 pages : 24 cm "The first sleep book by a leading scientific expert--Professor Matthew Walker, Director of UC Berkeley's Sleep and Neuroimaging Lab--reveals his groundbreaking exploration of sleep, explaining how we can harness its transformative power to change our lives for the better. Sleep is one of the most important but least understood aspects of our life, wellness, and longevity. Until very recently, science had no answer to the question of why we sleep, or what good it served, or why we suffer such devastating health consequences when we don't sleep. Compared to the other basic drives in life--eating, drinking, and reproducing--the purpose of sleep remained elusive. An explosion of scientific discoveries in the last twenty years has shed new light on this fundamental aspect of our lives. Now, preeminent neuroscientist and sleep expert Matthew Walker gives us a new understanding of the vital importance of sleep and dreaming. Within the brain, sleep enriches our ability to learn, memorize, and make logical decisions. It recalibrates our emotions, restocks our immune system, fine-tunes our metabolism, and regulates our appetite. Dreaming mollifies painful memories and creates a virtual reality space in which the brain melds past and present knowledge to inspire creativity. Walker answers important questions about sleep: how do caffeine and alcohol affect sleep? What really happens during REM sleep? Why do our sleep patterns change across a lifetime? How do common sleep aids affect us and can they do long-term damage? Charting cutting-edge scientific breakthroughs, and synthesizing decades of research and clinical practice, Walker explains how we can harness sleep to improve learning, mood, and energy levels; regulate hormones; prevent cancer, Alzheimer's, and diabetes; slow the effects of aging; increase longevity; enhance the education and lifespan of our children, and boost the efficiency, success, and productivity of our businesses. Clear-eyed, fascinating, and accessible, Why We Sleep is a crucial and illuminating book"--Provided by publisher Part 1. This thing called sleep : To sleep ... -- Caffeine, jet lag, and melatonin: losing and gaining control of your sleep rhythm -- Defining and generating sleep: time dilation and what we learned from a baby in 1952 -- Ape beds, dinosaurs, and napping with half a brain: who sleeps, how do we sleep, and how much? -- Changes in sleep across the life span -- Part 2. Why should you sleep? : Your mother and Shakespeare knew: the benefits of sleep for the brain -- Too extreme for the Guinness Book of World Records: sleep deprivation and the brain -- Cancer, heart attacks, and a shorter life: sleep deprivation and the body -- Part 3. How and why we dream : Routinely psychotic: REM-sleep dreaming -- Dreaming as overnight therapy -- Dream creativity and dream control -- Part 4. From sleeping pills to society transformed : Things that go bump in the night: sleep disorders and death caused by no sleep -- iPads, factory whistles, and nightcaps: what's stopping you from sleeping? -- Hurting and helping your sleep: pills vs. therapy -- Sleep and society: what medicine and education are doing wrong; what Google and NASA are doing right -- A new vision for sleep in the twenty-first century -- Conclusion : To sleep or not to sleep -- Appendix : Twelve tips for healthy sleep Includes bibliographical references and index