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Click the link in the description to start learning a new language today. [♪ INTRO]. Every night, people journey to an alternate reality filled with hallucinations and bizarre storylines.

It’s called dreaming. And scientists don’t know why we do it. I mean, it’s hard to study dreams, because it’s not like you can communicate back and forth with someone while they’re asleep.

Or at least you couldn’t, until now. In research published in early 2021, scientists figured out how to communicate with people while they’re dreaming. They even got sleeping people to solve math problems and relay the answers.

And their techniques could give us fascinating insights into why we dream and what happens in our minds when we sleep. Now, it wasn’t easy to get to this point. In the past, most dreaming research has involved asking people about their dreams after they wake up.

And as you might guess, that’s not really reliable. In other papers, scientists have attempted to interact with sleeping people. But the results of that haven’t been very exciting, either.

For instance, some studies have tried to influence people’s memory or behaviors by presenting them with sounds, spoken words, or smells while they slept. And they did have some success in influencing people’s ability to recall information or learn simple tasks when they woke up. But those experiments still only involved one-way communication.

The participants weren’t expected to communicate back while they were sleeping. That’s what makes the 2021 study remarkable. For the first time, scientists achieved two-way communication with dreaming participants.

The key to their success was that they focused on people experiencing lucid dreaming. During a lucid dream, people know they’re dreaming and have some control over the narrative. So, these researchers hypothesized that if a person has control over their consciousness like this, they might be able to answer questions about the dreamworld while they’re in it.

The problem is that lucid dreaming is fairly rare. Only 23 percent of people experience it once or more per month. And even if you’re prone to them, you can’t just summon a lucid dream whenever you want.

At most, you can train your brain to increase the likelihood of having them. And researchers have developed a few strategies for this. For instance, in what’s known as the reality testing method, you ask yourself throughout the day whether or not you’re dreaming.

The idea is that by doing this, you’ll build a habit and become more likely to automatically ask yourself the same question when you’re half-asleep. So you may catch yourself dreaming and become lucid. Unfortunately, this and other strategies aren’t especially reliable, which is partly why there hasn’t been a ton of research on lucid dreaming.

But in the 2021 study, researchers were able to pull it off. Four laboratories from around the world recruited 36 participants who had previously experienced lucid dreaming. The scientists knew that people typically have lucid dreams during the stage of deep sleep known as REM sleep, when their bodies are paralyzed, but their eyes can move.

So they trained participants to communicate using eye movements while they were awake. They taught them to signal they were having a lucid dream by moving their eyes left, then right, three times. They also trained them to use eye movements to indicate “yes,” “no,” and a series of numbers.

Then, the participants went to sleep in a lab and attempted to bring on a lucid dream. While they dreamt, the researchers asked them questions like, “What is one plus two?” or “Do you like chocolate?” The four labs used various methods to communicate these questions. Some used spoken words or beeping noises, while others used tactile stimuli or light that flashed Morse code.

And sometimes, the participants were able to interact with the researchers by incorporating those questions into the storyline of their lucid dreams. For example, one participant was looking at a cloudy sky in their dream. And when the researcher flashed a light, the dreamer transformed the sensation into sunlight flashing through the clouds.

Another participant approached a house in their dream. And when the researcher gave her a math problem, she transformed the address on the house into the math equation. Then, the dreamers relayed the answers by moving their eyes in that predetermined left-right pattern to indicate yes, no, or the specific number.

Not all the participants were able to achieve lucid dreaming or communication during the study. Because again, having a lucid dream isn’t that easy. But six of them correctly answered a total of 29 verbal and math questions during their dreams.

So, it’s a small start, but this experiment shows that, contrary to popular belief, it is possible to communicate with dreaming people. Plus, it shows that people are capable of pretty complex thinking while they’re asleep, like solving math problems in Morse code. Based on this, the researchers think people could be trained to use lucid dreams to solve problems that require creativity or to practice musical or athletic skills.

But more than that, this technique also gives scientists a new way to investigate questions like why we dream and what influences the storylines of our dreams. And that could open up a whole new world of study, and a whole new way to understand our brains. These days, most of our traveling might be done in our dreams, but if you want to prepare for a future time where you can explore the world, you might want to check out Babbel.

Babbel is a language-learning app, and it’s designed to help you quickly have conversations in a new language, like, after only five hours of practice. It’s the #1 language-learning app in the world, and currently offers 14 languages, from Spanish and French, to Italian, Portuguese, Russian, and more. The lessons teach you vocabulary and grammar skills that you can use in practical situations, like asking for directions or ordering food.

And the courses are also designed in a way that takes into account your native language, to make learning easier. If you want to check them out, you can download Babbel by clicking the link in the description. And as a thanks to SciShow viewers,.

Babbel will also give you up to 50% off a subscription at that link. [♪ OUTRO].