Can You Learn While You Sleep?

5 min read

Last Modified 7 October 2022 First Added 1 September 2014

By Liam Porter

While learning in your sleep, also known as hypnopaedia, may sound like the realms of a science fiction movie, it has been studied for over 100 years. Dating back to as early as 1914, research has concluded that sleep can help us learn.

Help is the keyword here. Because we must already access information before we can recall it during our snooze. Unfortunately, the question as to whether we can acquire brand-new knowledge during our slumber is still up for debate.

How does sleep affect learning?

Good quality sleep has a whole raft of benefits for our physical and psychological makeup. So it’s no surprise that healthier sleep habits enable us to recall more information that we’ve studied. Here’s a little on the science behind how and why adequate sleep often equals superior memory of knowledge…

Illustration of two sides of the brain

Sleep consolidates memory

Research shows that the brain is able to recall and retain information during sleep – or perform memory consolidation. This happens during deep sleep, the slow waves period of our sleep. Deep sleep consolidates short-term memory into long-term memory, originating in the neocortex and making a circuit with the hippocampus – the brain’s hard drive.


Scientists believe that this circuit allows for newly-learned information to be repeated and memorised during the deep sleep cycle, typically in the first half of the night. It’s been shown that patients with insomnia, who fail to reach the deep sleep stage of sleep, suffer from impaired memory consolidation.

Sleep helps us to retain the information that we have learned during the day. We know from animal experiments that new memories are reactivated during sleep. The brain replays previous experience while we sleep — and this replay strengthens memories overnight. – Science Daily

So, if we agree that learning is a process, rather than just exposure to new information, we can accurately state that we learn while sleeping. However, the key takeaway is that it’s only good quality slumber which helps us consolidate information.


Swiss National Science Foundation

Case study: Learning in your sleep

Research by the Swiss National Science Foundation claimed that listening to newly-learned foreign words while sleeping can help you improve your memory of them.

In the study, a number of German-speaking students were asked to learn Dutch words they had never heard of before at 10 pm.  Half of the group then went to sleep and had the words played back to them whilst they slept, while the other half were simply kept awake to listen to the words.

The first group was woken in the middle of the night and all students were tested on the new vocabulary. The scientists found that those who had listened to the Dutch words while sleeping were much better at recalling them than those who’d remained awake.

The number 1 tip for maximum sleep learning

Something is to be said for learning immediately before you go to bed. If you take in information just before bedtime, the brain can then store and compile it over a number of hours as you sleep.

This doesn’t mean that you’ll wake up instantly knowing everything you learnt the night before, but it will give you a much better chance of recalling information that has been committed to memory.

In her article 6 tips for the night before and the day of an exam Dr Susan Biali stated:

Sleep, particularly deep sleep, is critical for memory formation. New connections between brain cells form while you are sleeping, creating memories from your day. In order to reach the optimal number of cycles of memory-promoting deep sleep, aim to get a full eight hours before the big day. Make it a practice to get a good night’s rest after any intense day of learning and studying, as that will help your brain to retain as much information as possible.

Unfortunately, while good quality sleep can help us learn, poor sleep habits negatively affect our knowledge recall. Camille Peri, at WebMD, states:

“When people don’t get enough sleep, their attention and concentration abilities decline. Their reaction time lengthens, they’re inattentive, and they don’t respond as well to environmental signals. That means they can’t take in new information or react to dangerous situations.”

That’s because sleep deprivation, simply the act of not getting enough sleep, has a huge impact on how our minds and bodies work. This includes:

  • Our ability to concentrate
  • Our mood and emotions
  • Our likelihood of stress
  • Plenty of other bodily processes and factors which impact our ability to learn

Research by Paula Alhola and Päivi Polo-Kantola backs up this thinking, identifying how different levels of sleep deprivation have different impacts on our learning ability:

Total SD [sleep deprivation] impairs attention and working memory, but it also affects other functions, such as long-term memory and decision-making. Partial SD is found to influence attention, especially vigilance.


Yes, we can learn in our sleep. But we can’t acquire new knowledge, or at least science can’t yet prove it. If you need to maximise your ability to recall information for an upcoming exam or important day, it’s best to revise that information just before you go to sleep so your brain can actually process the new knowledge with ease during deep sleep.

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