Q&A: How Sleep Affects Memory

  • Written by: Amanda Myers


To understand how sleep affects memory, it is important to understand how the brain works when asleep.

Recent studies show that sleep has a big impact on most bodily functions including our brain where our memories are being processed.

Memory is part of our brains cognitive processes and plays a big part in several things including our learning ability. Imagine a day without the ability to remember what your brain just learned. Imagine learning how to read today and forgetting it tomorrow. Imagine how frustrating it is when your brain is slow in retrieving memories.

Our brain also helps us use memories and previous experiences in assessing new experiences. Our perception is largely based on our previous experiences. Without access to our memories, we lose the ability to interpret different situations which is important when we're making decisions.

Our brain and memories do these and more.

Questions & Answers

What happens to your brain when you sleep?

Sleep allows the brain to process new memories and store them for easy access in case you need to recall them.

Sleep also allows the brain to rest and be able to fully prepare to take in new memories once you're awake.

Different types of memories are processed in different stages of sleep. Having enough sleep does not only mean quantity (hours of sleep), but also quality.

Ask yourself: How many hours did you sleep and what kind of sleep did you get?

What are the two types of memories?

The two types of memories are fact-based and procedural. Fact-based memories include remembering dates or life events, while procedural memories include learning instructions and how-tos

What are the stages of sleep?

There are several stages, but there are 2 main stages of sleep and those are REM and non-REM.

Non-REM (includes deep sleep or slow-wave sleep) is responsible for processing fact-based memories.

REM (Rapid Eye Movement), which happens when you're dreaming, researchers say is responsible for procedural memories.

What happens to your brain if you lack sleep?

Most of you may have already experienced the following when you did not get enough sleep.

  • Brain becomes foggy
  • Poor judgment
  • Affects learning
  • Impairs ability to focus
  • Unable to recall memories
  • Slow cognitive speed

What would you recommend to those who are going to take an exam?

  • Avoid cramming.
  • You can't absorb everything in just one night.
  • Take it day by day.
  • Get enough sleep every day.
  • A quick review the night before the exam.
  • Give your brain enough sleep the night before the exam.

As they say, "Sleep on it" if nothing pops up out of your head.


Sleep helps your brain function better. Without enough sleep, your brain will have problems processing and recalling memories. Memory problems hamper our ability to learn.