Why we sleep

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. But an explosion of scientific discoveries in the last 20 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. Among so many other things, 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.