WHY WE SLEEP

Revelations about sleep that illustrate its vital importance to our brains, our bodies, and our lives.

The director of the Sleep and Neuroimaging Lab at the University of California, Walker has spent decades researching sleep and has served as a consultant to sports teams, financial institutions, and TV producers. In other words, he is an expert, but more importantly, he knows how to explain it all clearly to general readers. He begins by showing what sleep is and what it isn’t, how other creatures sleep, and how it changes across a lifetime. In Part 2, he examines the numerous benefits of sleep and how it affects mental and physical health, such as the ability to learn and the fitness of the gut and the cardiovascular and immune systems. So important is sleep to our well-being that Walker counsels that the shorter one’s sleep, the shorter one’s life span. In Part 3, which peers into the brains of people dreaming, Walker provides examples of the sometimes-astonishing creativity and problem-solving power of dreams. This section also tackles the phenomenon of lucid dreams—i.e., dreams controlled by the dreamer. In Part 4, the author takes up sleep disorders and the harmful effects of sleep deprivation, not just to the individual, but to society. Walker counsels against sleeping pills and offers nondrug therapies that he has found to be effective. In the concluding chapter, “A New Vision for Sleep in the 21st Century,” the author outlines his proposals for enhancing sleep quantity and quality: individual use of new technology, sleep education in schools, sleep reform in the workplace, public campaigns to heighten awareness of the hazards of drowsy driving, and, more elusive, societal change in sleep awareness. Readers, he cordially advises, may read the parts in any order they prefer and close their eyes and take a nap if they feel like it.

Though readers seeking dream interpretation will be disappointed, Walker provides a well-organized, highly accessible, up-to-date report on sleep and its crucial role in a healthy life.