Is it possible to learn while sleeping

It turns out there actually are a few things you can learn - or at least improve your grasp of - while you snooze. Most of them depend on one thing: sound. Here are some of the skills you may be able to sharpen in your sleep. In a recent experiment, scientists had native German speakers start learning Dutch, beginning with some basic vocab.

Then they asked them to go to sleep. Unbeknownst to the dozing Germans, while they slept, the researchers played the sound of some of those basic words to one group of them. The other group was exposed to no such sounds. Later on when they were tested on the words, the group that had listened to them overnight was better able to identify and translate them.

To make sure the findings were tied to sleep - and not just the result of people hearing the words - they had another group listen to the words while they did something else while awake, like walking.

The walkers didn't recall the words nearly as well as the sleepers. Nevertheless, if you've been learning vocabulary in a foreign language, it can be highly effective to hear these words played over again while you sleep, as was already shown a year ago by researchers from the university of Zurich and Fribourg.

Their new study, funded by the Swiss National Science Foundation, demonstrates that this only works if the brain can do its job undisturbed. The researchers got 27 German-speaking test subjects to learn Dutch words, then let them sleep for three hours in the sleep lab. The scientists already knew that playing back this vocabulary softly would help the test subjects to remember the words. Now they wanted to give them more information while they were asleep. They also wanted to achieve the opposite -- in other words, they hoped that supplying incorrect translations would make the test subjects forget what they'd learned.

He was able to confirm the original findings -- that simply cuing the Dutch vocabulary during sleep enabled the subjects to recall about ten percent more words. He and his team have concluded that it's not the total information offered to the brain that is important.

Instead, the brain just needs a nudge in order to enhance the ability to recall. Unless you want to record lists of vocabulary to play back to yourself every night, it sounds as if we should retreat to our waking hours to learn a language. Many people are familiar with the REM phase of sleep, which is when most dreaming occurs, but a lesser-known phase is slow-wave sleep, or SWS.

Researchers have found SWS to be an important phase for memory processing. Jakke Tamminen , a psychology lecturer and researcher at Royal Holloway University of London, studies how sleep affects learning and the role memory consolidation plays in that process. They were words from a fictional language with a hidden rule binding them together.

The study found that participants in the experimental group were able to understand and apply the rule while sleeping and were better able to recall the words they learned than those who did not sleep. Memory consolidation is linked to what are called sleep spindles , or short bursts of brain activity that occur during the SWS phase of sleep and are involved in the reactivation of new information.

The study found that participants who exhibited the highest number of sleep spindles showed the most signs of integration between existing memories and new ones, which helped them retain the new vocabulary. So while some CEOs are adamantly anti-sleep, trying to optimize every hour of your day might not be the best approach. While you could technically put on an eight-hour YouTube video of Spanish vocab before you sleep, you might end up disappointed by how little you recall. After this, when awake, the people performed better than chance when they had to pick the right translation of made-up words in a multichoice test.

What all these studies have in common is that they show an implicit form of memory. Learning a new language involves many different layers: recognizing the sounds, learning the vocabulary and mastering the grammar.

So far, research suggests it may be possible to get familiarized with the tone and accent of a language or even the meaning of words while sleeping, but to a weaker level than what we already do all the time during the day without noticing. And then you have to consider the cost, Andrillion said.

Stimulating the sleeping brain with new information likely disrupts the functions of sleep, negatively affecting the pruning and strengthening of what we have learned over the previous day, he said. While losing quality sleep to potentially learn a few words is not a smart trade-off, researchers continue to study sleep learning because the compromise may be worth it in special cases.

For example, sleep learning could be useful when people need to change a habit or alter stubborn disturbing memories in cases of phobias and post-traumatic stress disorder. And some forms of implicit learning that may help in those situation may occur more strongly during sleep. The conditioning that happened in the smoking and rotten egg study, for example, doesn't work well when done during wakefulness.

If you smoke every day near a garbage bin, you know the two are unrelated, so you don't link them. We are not easily tricked when awake.