Written by: Stephanie Young
Updated March 18, 2021
A good night of sleep provides numerous benefits. In addition to leaving you feeling rested and rejuvenated, quality sleep can enhance your memory organization (1). You may even be able to learn new information in your sleep (2).
While you are sleeping, your brain actively works (3) to process the information you gathered throughout the day and prepare for your upcoming day. If you have ever been sleep deprived, you might recall the negative effect it had on your memory and brain function the following day.
How Does Sleep Affect Memory?
Your brain is not idle while you are sleeping. In fact, the hippocampus (4), which supports long-term memory formation, is even more active during deep sleep than during wakefulness. There are several processes that happen during sleep that affect your memory.
Slow-Wave Sleep (NREM or Non-Rapid Eye Movement)
Research shows that deep, slow-wave sleep may be the most favorable for enhancing declarative memories (5). Declarative memories (6) allow you to consciously recall facts and events from everyday life.
The four stages of NREM sleep (7) last about 70 to 90 minutes for the average sleeper and primarily happen during the first few hours of sleep. The last two stages of NREM sleep combined are considered slow-wave sleep (8), which is the stage of sleep that is said to be the most conducive to learning verbal information.
Rapid Eye Movement (REM)
REM is the stage of sleep in which our most vivid dreams typically occur. The average sleeper spends about 20% to 25% of sleep time in the REM stage (9). Sleep during REM seems to enhance a different type of long-term memory called procedural memory (10). Procedural memories help you recall how to perform certain tasks, such as how to ride a bike, walk, or talk.
Sleep plays an important role in building memory. Recent research suggests that the waking brain enhances the encoding of memories (11), while the sleeping brain enhances memory consolidation. During slow-wave sleep, our recently encoded memories are reactivated and transformed into long-term memories. Once we move into REM sleep, those transformed memories start to stabilize.
Can You Learn While You Are Sleeping?
Research supports the idea that sleep enhances memory, and suggests that it is possible to learn new information while you are sleeping. Findings suggest that the same parts of the brain that support vocabulary learning while awake also support vocabulary learning during sleep. However, the retrieval of the learned information may only be available at a subconscious level.
Can You Learn a New Language in Your Sleep?
At this time, the evidence surrounding language learning during sleep is inconclusive. There may be some level of subconscious learning taking place, but without being able to retrieve the information again at a conscious level, you aren’t likely to have much success. Generally, events occurring in our sleep are neither remembered nor recognized the next day.
Although learning in our sleep may not achieve the desired results for conscious retrieval of information, subconscious learning can still make an impact. For example, one study exposed sleepers who are habitual smokers (12) to cigarette smoke paired with unpleasant odors. Over the next several days, the participants’ cigarette consumption significantly reduced. This conditioning technique was only successful when applied during sleep and unsuccessful when applied while awake. This evidence suggests that subconscious learning during sleep may influence behavior when awake.
How Can You Sleep Better to Improve Learning and Memory?
Knowing that quality sleep is vital in many ways, it is important to make sleep a priority for your wellbeing. If you are not currently receiving optimal sleep, these suggestions from the Centers for Disease Control and Prevention (CDC) may help improve your sleep hygiene:
- Be Consistent: Try to go to sleep and wake up around the same time each day.
- Improve Your Bedroom Environment: Make your bedroom dark, cool, and quiet. Remove electronic devices such as TVs, computers, and cell phones.
- Avoid Drinks that Affect Sleep: Avoid caffeine and alcohol before bedtime.
- Exercise Regularly: Adding physical activity during the day can help you sleep better at night.
How Does Sleep Affect Learning and Memory?
Sleep is an integral key to maintaining mental and physical health. Certain stages of sleep enhance your memory in different ways, and it is possible to learn new things while sleeping (at least on a subconscious level). Research also suggests that you have better overall productivity if you get some quality sleep — even a quick nap aids in the consolidation of new memories.
- https://pubmed.ncbi.nlm.nih.gov/24782726/ Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/22922782/ Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/26029150/ Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/31954628/ Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/19251443/ Accessed on March 13, 2021.
- https://www.nimh.nih.gov/research/research-funded-by-nimh/rdoc/constructs/declarative-memory.shtml Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/10554397/ Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/30836087/ Accessed on March 13, 2021.
- https://www.ncbi.nlm.nih.gov/books/NBK19956/ Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/17905642/ Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/23589831/ Accessed on March 13, 2021.
- https://pubmed.ncbi.nlm.nih.gov/25392505/ Accessed on March 13, 2021.