Can We Learn New Foreign Words While Asleep?

Every day we get to learn something new or the other, but did you know you could learn even when you are asleep? Sounds too good to be true? But it’s proven now! Researchers suggest that sleep plays a vital role in the learning process, and it can help you grasp new words and information during deep sleep. This is because the brain’s learning channels are open even during sleep.

While we are asleep, our brain organizes and consolidates events and information we encountered throughout the day. Important, relevant information is filed away, while things that are of little or no importance are eliminated in the process, making room for new learning.

Establishing a Connection between Sleep and Learning

A study was conducted on 41 healthy females and males to examine whether humans can establish a meaningful connection between foreign words or language and their translation in deep sleep or slow-wave sleep – the stage where people are not much conscious of their surroundings. German-speaking participants were put to sleep to the audio clip of pairs of pseudowords for non-existent foreign words and their meaning. The objective of the study was to find out if these words would leave a trace on the participants’ memories, even when he/she was unconscious. After waking up, the participants were given the pseudowords (this time without the translation). The participants had no knowledge of the recording being played during their sleep; therefore, they were not aware that the brain had heard some of these words earlier. They were asked to imagine the object denoted by the pseudoword and guess whether it was larger or smaller than a shoebox. This approach allowed the researchers to tap into the participants’ unconscious memories.

Researchers found that participants were able to classify the foreign words correctly, at a 10% higher accuracy rate than random chance, for as long they heard the words precisely during deep sleep. This suggests that the approach caused the brain to create memory traces or a few changes in the portion of the brain that stores memories. For example, if you present the sleeping participants with two words, ‘bird’ (a known word) and ‘biktum’ (a pseudoword), then their brain can form an association between the two. This memory trace formed during sleep continues into the following wakefulness and influences the way you react to the foreign word (in this case, ‘biktum’ is the word) although you might think you have never heard of that word before. It is an unconscious, implicit form of memory, pretty much like a gut feeling.

Timing is Crucial

When you are in deep sleep, your brain alters between ‘down state’ and ‘up state’ every half a second. The brain is interconnected and highly active during the up states, which means it is at the prime of learning new stuff. The more you hit an up state, the better you memorize things. To put it simply, people are more likely to classify the words they hear during the peak of one’s slow wave sleep correctly than the ones they hear during the periods when the brain activity is less optimal.

The study indeed gave us a striking revelation – the concept of ‘sleep learning’ may be more than just fiction. However, whether one can learn explicit information and new foreign words faster during wakefulness, provided the words/information are already presented to them during sleep, is yet to be examined.