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Gamma Wave Brain Zaps Induce Lucid Dreaming

ByAllison EckNOVA NextNOVA Next
Lucid dreamers are aware that they're dreaming—which means it's possible for them to influence which path the dream's story will take.

Some people have as much fun in their dreams as they do in real life.While sleeping, they might change the direction of their dream’s storyline, fly to remote places, explore untrodden territory, or encounter strange creatures. They’re like film directors, guiding the artistic vision of their subconscious.

Such creative license is thanks to a state of mind called lucid dreaming. A lucid dreamer knows that what she’s seeing and feeling is a dream, not reality—and with that awareness comes the ability (in some lucid dreamers) to make decisions about the dream’s course of events. This sensation is difficult to reproduce in people who aren’t naturally lucid dreamers—in other words, for anyone who’s never had this experience, it’s a hard skill to acquire. But clinical psychologist Ursula Voss and her colleagues at Frankfurt University in Germany claim to have found a way.

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Here’s Virginia Hughes, writing for National Geographic:

In this study, Voss and her team recruited 27 healthy young adults who had never experienced lucid dreaming. Each participant slept overnight in the lab on several occasions. Two minutes after reaching the REM (rapid eye movement) stage of sleep, which is when dreaming happens, the subjects received a weak electrical current (2 to 100 Hertz) to the frontal lobe for 30 seconds, or a sham current with no electricity.

The sweet spot was 40 Hertz. Zapping sleeping volunteers at this frequency, part of the so-called gamma wave band, led their brains to produce brain waves of the same frequency, the researchers found, which triggered lucidity 77 percent of the time, as determined by self-reports from the dreamers after they were awoken.

Voss had actually pinpointed the 40-Hz currents as lucidity generators in 2009 when she observed that veteran lucid dreamers produced 30- to 40-Hz brain waves in their brain’s frontal area. Until now, though, scientists couldn’t be sure that those waves caused lucidity or if that kind of brain activity was a mere side effect.

Does that mean you could someday, after a mere zap to the brain, become the commander-in-chief of your dreams? It’s not certain, writes Christian Jarrett for Wired:

Despite the robust methodology, I think these headlines are getting carried away. Here’s why. Lucid dreaming was defined by higher scores in participants’ feelings of insight (knowing that they were dreaming); dissociation (taking a third person perspective); and control (being able to shape events). I looked up the paper where the researchers first described their scale for measuring these factors. If I understand correctly, the participants rated their experience of these three factors on a scale of 0 (strongly disagree that I had such an experience) to 5 (strongly agree). Now if we look to see the scores they gave for how much dream insight, dissociation and control they had, we find that the averages for the gamma stimulation condition are around 0.6, 1.3, and 0.5 respectively.

That’s a pretty low score, even if it’s higher than it would’ve been without the brain stimulation. Nevertheless, induced lucid dreaming to any extent is fertile ground for neuroscientists who want to solve the mysteries of consciousness. So while we might be far from DIY dreams, we might be closer to understanding why we dream in the first place.

Photo Credit: Vinoth Chandar / Flickr (CC BY 2.0)

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