Exactly how lucid dreaming works in the brain is still something of a mystery. Research shows that lucid dreaming stimulates the mind in the same ways as waking life. If you sing during a lucid dream, for example, the right hemisphere lights up, just as it would if you were awake. If you do math, the left hemisphere becomes active. And the effects reverberate through your body even after you wake up. It can, for instance, improve motor skills. Sleep researchers at Heidelberg University proved that practicing a task in a lucid dream—tossing a coin into a cup—makes the dreamer significantly better at it during waking hours. They're currently experimenting with more complex tasks, like running and jumping, to see if eventually athletes might be able to train in their sleep.

But the real power of lucid dreaming, according to those who've mastered it, is how it alters your perception of, well, pretty much everything.

"When I'm flying in a dream, what's moving?" asks Robert Waggoner, the author of Lucid Dreaming: Gateway to the Inner Self and a popular speaker on the lucid-dream lecture circuit. "What's the nature of space in a lucid dream? It's just a mental construct. Early lucid dreamers, the Buddhists who practiced dream yoga, they wouldn't even bother to fly to the mountain in their dreams. They'd just pull the mountain to them."

"It does tend to blur the lines between reality and dream life," agrees Sean Kelly, a 27-year-old longtime lucid dreamer from California who studied perception and cognitive science at the University of California, Berkeley, and now splits his time between Thailand and India, studying yoga and consciousness. "Not to the point where you can't function. It's not like, 'Oh my God, I can't cook this egg because I don't know if it's real.' But when you start to experience a lucid dream—consciousness without being encased in a physical body—it starts to shift your idea of the world, of what reality really is. Reality in a dream and reality in the physical world—they're both constructs of your consciousness. You start to realize that we don't have any idea at all what reality really is."

If taking flight via lucid dreaming sounds like a different sort of trip, there's a reason.

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"I was climbing K2 and there were snowdrifts all around," says Dr. Stephen LaBerge, recalling the dream that would ultimately bring LD into the mainstream. "But I was dressed in shorts. And I thought, 'Wait a minute, I'm not properly prepared to go to the top of a mountain. Of course, it's a dream!' I was so reeled by it, I just flew off the mountain."

Meet the godfather of lucid dreaming, the researcher who brought LD from the fringes of alternative psychology to the razor-sharp edge of modern sleep and dream science. LaBerge, who bears a passing resemblance to Christopher Lloyd's Doc from the Back to the Future movies (though he drives a Subaru, not a DeLorean), is 67 now, living in Arizona and leading seminars. His dream about climbing K2 in shorts came when he was a graduate student in chemical physics at Stanford in the late sixties. Like so many others of his generation, he was drawn to psychedelics—only in his case, as a subject for study. He was researching their effects on consciousness. The substances, though, were illegal, making research difficult. LaBerge's eureka moment—his mountain-climbing dream—"set the seed," he says. "I couldn't study psychedelics, but here was a state—one that happens naturally in the rem cycle—that had similar potential."

The breakthrough came in the early eighties, while LaBerge was conducting research at Stanford's prestigious Center for Sleep Sciences and Medicine. He had come up with an ingeniously simple study that proved once and for all the reality of lucid dreaming: Subjects with a history of lucid dreaming were given instructions to send specific signals—two pairs of left-to-right eye movements—once they slipped into the deepest level of REM sleep, where lucidity occurs. "That was something," LaBerge recalls proudly. "A communication from the dream world while it was happening."

He spent the following decades sharing his findings in books (Lucid Dreaming, Exploring the World of Lucid Dreaming), establishing the Lucidity Institute, and inventing devices like the NovaDreamer, a now-discontinued sleep mask designed to nudge dreamers into lucidity with light pulses powerful enough to penetrate the unconscious and alert dreamers that they're asleep, but not so disruptive as to wake them.

Whether you're delivered there by light or by luck, the moment you achieve awareness that you're in a dream is when it becomes lucid. LD practitioners train themselves to recognize dream signals—in my case, an office cubicle in the middle of a forest; in LaBerge's, inappropriate mountain-climbing attire—that tip them off to the fact that they're dreaming (think of them as unreality checks). Sean Kelly suggests giving yourself the finger: He pushes his middle finger into the flesh of his palm, and if it goes through, he knows he's dreaming.

During my first few unsuccessful weeks attempting lucidity, none of this worked. Nor did the Remee, a red-light-emitting LD mask made by a Brooklyn company, which just kept me from sleeping at all.

There is another, chemical option for those stuck on the lucidity launchpad, something that several lucid dreamers had quietly clued me in to: galantamine, a brain-boosting drug used as a treatment for Alzheimer's that's said to have powerful lucid-dream-triggering side effects. Like many other nootropics, a.k.a. smart drugs, galantamine requires a prescription in the U.S., but low-dosage capsules containing its active ingredient—derived from the flowers of the Galanthus causcasicus plant—can easily be obtained. You wake up to take it at three in the morning, then go back to sleep, perchance to lucid-dream.

It didn't have an effect on me, at least not initially. But then, a couple of nights later, when I wasn't expecting it, I had my lucid dream. It may have been a delayed reaction to the galantamine. Or perhaps it was simply because I'd been concentrating on lucid dreaming so intensely (all the experts agree that a strong desire to lucid-dream is a key factor in achieving lucidity)—and on my looming deadline. But there I was, in a cubicle in the forest, typing these words into a laptop: This is exhilarating. Although next time, I want to try to dream bigger. I'm going to fly.

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