The Science of Sleep: What It Is, How It Works, and Why It Matters

We often hear that humans spend one third of their lives sleeping—and most of us would up that fraction if we could. Whether we’re curling up for a brief lunchtime catnap, catching a doze on a sunny afternoon, or clocking our solid eight hours at night, sleeping is normally a reliable way to rest our heads and recharge our minds. And our bodies demand it: without sufficient sleep, we experience changes in mood, memory loss, and difficulty concentrating. Symptoms of sleep deprivation can be ...