You may have heard of lucid dreaming, the type of dream where the dreamer is aware of dreaming. Is lucid dreaming a real phenomenon? Sleep expert Matthew Walker explains how much we know about lucid dreams so far. Following is a transcript of the video.
Jessica Orwig: What if we could control our dreams?
When most of us dream, our thoughts and actions are involuntary. The dream plays out as if we were watching a movie. But not all dreams are the same. There is another kind of dreaming called lucid dreaming, which is more like playing a video game than watching a movie.
Matthew Walker: By definition lucid dreaming is simply the act of knowing that you're dreaming whilst you're dreaming.
My name is Matthew Walker. I am a professor of neuroscience and psychology at the University of California Berkeley.
Most people actually think of lucid dreaming more in the sense of actually beginning to control what you're dreaming. So, you gain volitional control and you decide what's going to happen during your dream.
Orwig: Frequent lucid dreamers claim that they can control many parts of the dream such as teleporting themselves to another location, learning to improve real-life skills, or even eating fire. It might sound far-fetched. And until recently we lacked the technology to prove if lucid dreaming was real or not. But a series of recent studies has shed light on the phenomenon.
Walker: Scientists have designed experiments and they've been able to demonstrate objectively that when people say that they're doing something in that dream that they actually are.
Orwig: In 2012, scientists reported results from one of the first experiments that objectively measured lucid dreams using fMRI scanners. fMRIs measure the rate of blood flow to different areas of the brain, so they can relay information about a person's thoughts and actions simply through a series of images.
For the study, scientists first asked participants to clench their fists while they were awake. This lit up key areas of the brain on the fMRI scanner. After that, participants were asked to fall asleep and dream about clenching their fists. Sure enough - similar regions of the brain lit up in both cases.
Lucid dreaming comes naturally to some, but many of us have never experienced the sensation. However, that doesn't mean it's impossible.
Walker: How can we actually become more capable of lucid dreaming? Well, it's a little bit tricky, but you can certainly try to tell yourself that you will remember that you're dreaming whilst you're dreaming before you actually fall asleep. So, try to go through a mantra chant as it were. Some people actually try to do deliberative things whilst sleeping, like turning on the lights in a room. And that helps them to become aware that they are dreaming at the moment of dreaming itself and therefore they gain lucid control.
Orwig: Those who can already control their dreams with ease say lucid dreams aren't only for entertainment but can also be used to expand one's conscious boundaries.
On the other hand, lucid dreamers have also reported frightening accounts where they have trouble distinguishing reality from the dream. In some cases, this can be a sign of mental illness, and should be taken seriously.
But why do some people have the ability to lucid dream but not others? And what is happening in our subconscious that triggers the experience? There's still a lot we have to learn about the causes and effects of lucid dreaming.
Walker: It seems to be only around 20 to 30% of the population are actually natural lucid dreamers. So, perhaps if it was so beneficial mother nature would have had all of us being table of lucid dreaming. And the fact that we're not perhaps means that it's not necessarily beneficial. But we actually don't know. Maybe those 20 to 30% of people who do lucid dream are at the forefront of hominid evolution, and they are going to be the next species of preference. We just don't know.