Why We Sleep

Why We Sleep

Unlocking the Power of Sleep and Dreams

Book - 2017 | First Scribner hardcover edition
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" Why We Sleep is an important and fascinating book...Walker taught me a lot about this basic activity that every person on Earth needs. I suspect his book will do the same for you." --Bill Gates

A New York Times bestseller and international sensation, this "stimulating and important book" ( Financial Times ) is a fascinating dive into the purpose and power of slumber.

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.
Publisher: New York : Scribner, 2017
Edition: First Scribner hardcover edition
ISBN: 9781501144318
Branch Call Number: 612.821 W18w
Characteristics: viii, 360 pages : illustrations ; 24 cm


From the critics

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Mar 29, 2021

Fabulous read. It certainly made me look again at my sleep patterns. And purposely adjust a few. For anyone interested in having quality health, I urge them to read this top quality book

Mar 20, 2021

I've been engaged with my own, personal, small-scale sleep experiments for a long time. Almost a decade ago, I created this weird alarm clock called "Sense Alarm", that leverages the power of your other senses, not just your sense of hearing, to wake you up - http://anoopdixith.com/sensealarm/. But I have never been able to dissect the internals of sleep in a more scientific way, although forever and a day I wished I could. So, what better way to learn more about sleep and a gazillion other sleep experiments than from Dr. Matthew Walker, who has been studying sleep for over thirty years and has written over a hundred research papers on the topic? For the interested ones, his website is aptly titled sleepdiplomat.com. The author has also been a sleep consultant for NBA and NFL teams, military etc, for all those who thought this isn't a lucrative business. The book turned out to be a captivating read as expected, neither hardcore technical like a textbook nor shallow like a popular science book. And I ended up taking more notes than probably any other book I have read this year.

The book is very logically divided into four segments, each dealing with a unique aspect of sleep - its importance, its effects, its abnormalities like insomnia, somnambulism, narcolepsy, sleeping-aids etc, and social aspects of sleep. I think the author has done a tremendous job squeezing in every aspect of this universal, ultra important, metabolic activity - jet-lags, caffeine, sleep with aging, sleeping pills, light-heavy gadgets, sleep deprivation in US medical residents (about which I've first hand experience), Alzheimer's, negative impact of the snooze in alarm clocks etc. But we definitely need to give a special shout out to the last chapter - "Vision for 21st century" where the author tries to offer solutions to the contemporary sleep problems in the society at the individual, business, education, and societal levels. I must acknowledge that many solutions proposed are indeed considerable and sufficing, if not revolutionary. And just like all the matters of sleep, with time, even minor improvements applied consistently make a colossal positive difference. The book also does a marvelous job of theorizing something and then backing it up with a plethora of experimental results, and many of the theories are the author's very own, which is by far the best you could get out of a nonfiction book.

As far as the content of the book goes, even after reading the entire book, or maybe even after going over a hundred scholarly papers on it, if you ask me to answer in a line why we sleep, I wouldn't be able to. The book doesn't either. It's definitely a longer answer. But that's because like most things related to the brain, sleep, which is in fact mostly related to the brain more than any other activity like breathing, motory skills etc, is just a very elusive topic that is still very much under active research. But like the author puts it, it has to be an ultra important process and would be considered "evolution's biggest blunder if it has no use". Following are some of the main points distilled from the book -

1. All organisms sleep - there's no organism with a nervous system found yet that doesn't sleep. That probably means sleep was developed very early in evolution, and couldn't possibly have no direct or indirect impact
2. Not just animals, but plants also have circadian rhythm, that operates independently of its solar exposure
3. Being a night owl or a morning lark is genetic. It's in our genes to wake up early or go to bed late. Evolution made it that way so, as a tribe with both kind of animals, humans could be awake for a longer span overall to protect ourselves from predators
4. Repeated experiments have proven that the human circadian cycle is 24 hours 15 mins, although the stellar day is 23 hours 56 minutes and 4.09 seconds long. The flexibility in this is still unanswered.
5. Adenosine build-up and the circadian rhythm together causes s

Mar 16, 2021

This is a fascinating book about how the brain and sleep works. Although it touches on dreaming it's more about how less or more sleep affects the brain and in turn our ability to function (or not).

FPL_Annie Oct 29, 2020

It turns out, if you don't sleep, you will die!

Oct 22, 2020

This book is an engaging read on an important topic. However, it's not clear how strong the science is in support of some of Walker's key points because he doesn't provide many references. When he does provide a reference it's often to one or a few small studies or in non-representative populations, e.g. college undergrads. Walker's arguments mainly make intuitive sense and seem to be consistent with what one would expect science to support, e.g. caffeine is bad for sleep hygiene. Unfortunately, Walker generally doesn't always provide the evidence to solidly back his claims, especially on more esoteric matters. Still, this book is a thought-provoking and worthwhile read.

Sep 30, 2020

Why We Sleep is a book by Professor Matthew Walker, Director of UC Berkeley’s Sleep and Neuroimaging Lab. As the title suggests the book explores why we sleep. This question is much more difficult to answer than one may think. In this book Matthew Walker answers the many questions you may have about sleep and also answers the questions you did not even know you wanted to ask. He covers the effects of alcohol and caffeine, the innumerable benefits of sleep and what actually happens when you sleep. Many people think sleeping for 8 hours a night is lazy and unproductive but in reality only getting 6 hours of sleep hinders almost everything, from memory to creativity to your ability to control emotions. I would recommend this book to everyone as the effects of such a simple thing are truly eye opening. I give Why We Sleep five out of five stars.
@Nessie of the Hamilton Public Library's Teen Review Board

Loganlib_Brad Sep 06, 2020

Really enjoyed this, covers a lot of interesting ground. Definitely gets you to think more seriously about getting a good nights sleep, but also throws light on how little we value good sleep as a society.

Aug 02, 2020

A friend highly recommended this book and, boy, was she spot on. This should be taught in school for sure. Part I This Thing Called Sleep was my favorite section. I found it very interesting and informative.

IndyPL_TimothyV Jun 30, 2020

Dr. Walker presents the results of research on sleep in a way that is both engaging and informative. The careful reader will emerge with a much more thorough awareness of how sleep impacts nearly every aspect of life.

Mar 08, 2020

My go to for information

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Aug 02, 2020

A balanced diet and exercise are of vital importance, yes. But we now see sleep as the preeminent force in this health trinity. The physical and mental impairments caused by one night of bad sleep dwarf those caused by an equivalent absence of food or exercise.

Dec 20, 2017

Neuroscientist Matthew Walker, PhD, expands our knowledge and emotional connection to the sleep that occupies so much of our lives. He draws amazing pictures of the work our brain completes during different cycles of sleep, and as a passionate advocate of health, he makes recommendations about public policies that could protect us.

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