You might find yourself tumbling down an endless void. Or you’re being chased by a seriously annoyed alligator. Maybe you’re even back in school, about to take a history exam without having studied — and, yes, you’re also completely naked.
Whether it’s about a long-lost acquaintance or bees with teeth (don’t ask), dreaming is one of the oddest things we do. These nocturnal hallucinations tend to be most vivid during a kind of sleep called rapid eye movement (REM). And even when we don’t remember them, most of us typically spend around two hours each night dreaming. But why do our minds race even while we’re sound asleep?
Humans have been musing on the reasons behind these nightly mental jaunts for millennia. If you plug “why do we dream” into Google, you’ll get nearly 4 billion — specifically, around 3,610,000,000 — hits. But even today, scientists still don’t entirely agree on the purpose of dreaming. By contrast, there’s loads that we do know about the role of sleep, which has been found to help boost brain function, regulate our immune systems and promote physical activity. The study of dreams is particularly daunting because scientists often have to rely on reports from recently awakened subjects.
