The link between sleep and memory was first established years ago. That said, since scientists are not entirely sure how our brains retain memory, the exact relationship between sleep and memory is still being investigated, and is not completely understood.
What we do know is this: more sleep can mean better memory.
Sleep critical for memory function
Despite the unknowns, the general consensus among scientists is that sleep enhances your brain’s ability to remember information and, therefore, to learn.
Conversely, a lack of sleep negatively impacts your ability to secure memories and can interfere with learning. Sleep—and different sleep stages in particular—appear to allow the brain to re-process newly acquired information into more lasting memory.
During this process, memories made during the day are said to be “consolidated,” or crystallized into long-term, stable memories. The quality and quantity of our sleep affects our memory, no matter how old we are.
More sleep, better skills
Research shows that sleep can enhance motor memories. Motor memory, also known as procedural memory, refers to the ability to learn physical skills like riding a bike, throwing a baseball, mastering a video game or playing an instrument. Sharp motor memory can help people who are training for a sport or learning new musical pieces on the piano. If you get enough sleep, your skill-based memories become sharper. Motor memories can even benefit from an afternoon nap, which is often dominated by light sleep.
Sleep improves recall
Declarative memory refers to the ability to store and recall facts, such as all those dates, places and events you had to memorize in history class. Research has found that memories of recently learned facts strengthen if sleep occurs between learning and testing. During deep sleep, (slow wave sleep), declarative memory appears to be given a particular boost. College students take note: an all-nighter may not be your best strategy! Your recall for facts will be greater if you allow yourself a good night’s rest before an exam.
Perceptions influenced by sleep
Perceptual memory can also be enhanced by sleep. It has been suggested that during REM sleep, the brain processes sensory learning, which can lead to better understanding of the visual, auditory, spatial, and emotional conditions that surround us. The S+ presents a Mind Recharge score that is based on your REM sleep.
Memories made during sleep?
Even though sleep can be very beneficial for strengthening memories, it is not a great time for new memories to form. As the body transitions between sleep and wakefulness, the brain’s ability to retain new information shuts down.
Case in point: Have you ever woken up late in the morning only to realize that you had turned off your alarm without realizing it?
You probably fell asleep again so quickly that your brain had no time to store the memory of the alarm ringing. This may also be the reason why you don’t always remember your dreams, or they tend to fade very quickly in the morning. The transitions between sleep and wakefulness make the formation of new memories a challenge.