Your Brain: The Missing Manual

Dream Analysis

The most obvious hallmark of REM sleep is irrational dreaming with vivid, hallucinatory detail. However, it's quite possible that REM sleep isn't designed to create dreams. Instead, dreams might simply be a side effect of the lower-level brain processes that are going on during REM sleep (possibly memory consolidation and emotional regulation). As your brain is flooded with a chaotic series of images and memories, the reasoning centers of your brain do what they're trained to do—they struggle to make sense of the disorganized mass of information by weaving it into a barely logical story.

Even if dreams aren't anything more than noise in the higher regions of your brain while the older, more primitive levels do their housekeeping, they can still be mind-bendingly fascinating. Dreams can also be useful, by providing insight into your emotions or giving you a burst of creative thinking.

The Content of Dreams

Although you undoubtedly remember a few of your most memorable dreams, you probably don't have as good an idea about the overall pattern of your dreaming, and how your dreams compare to the nightly visions of other people. Large dream studies shed some light into these questions by comparing the dream journals of hundreds of volunteers, sometimes over long periods of time. Here are some of their discoveries:

• There's not much sex. Sure, it happens, but not nearly as often as a lusty Freudian psychiatrist might have you believe. (That said, sex plays a commanding role ...