REM Sleep vs. Non-REM Sleep: What’s the Difference?
Getting good sleep is incredibly important for our overall health and well-being. When most of us think of sleep, we usually think of two stages: REM sleep and non-REM sleep. But what’s the difference between these two stages?
REM or Rapid Eye Movement sleep and Non-REM (or NREM) sleep refer to the different stages or phases of our sleeping cycle. While Non-REM sleep is deep and non-interruptible, REM sleep is much lighter and more easily disturbed.
The two stages together make up our complete sleep cycle, and we’ll usually experience them several times during the night. Let’s take a closer look at each stage to better understand the difference.
Non-REM Sleep
Non-REM sleep or NREM sleep is generally deeper and is divided into three stages: N1, N2, and N3. N3 sleep is also known as “slow wave” or “deep sleep”. This is the stage where restorative and restful sleeping occurs.
During the Non-REM stage of sleep, our body temperature and heart rate drop, breathing slows, and major organs and muscles become relaxed. While here, our bodies are healing and restoring themselves which enables us to function better the following day.
REM Sleep
REM sleep or Rapid Eye Movement sleep is the stage we usually associate with dreaming. It gets its name from the rapid eye movement behind our eyelids that occurs during this stage. Most of our dreaming occurs during REM sleep, which usually begins 75 minutes after we initially fall asleep.
REM sleep is significantly lighter than non-REM sleep and it is easier to awaken or disturb someone during this stage. During REM sleep, our brain activity increases dramatically and our breathing and heart rate quickens. It is also during this stage that our muscles tend to be more active as they relax and our arms and legs temporarily become paralyzed.
The amount of time we spend in REM sleep is something that increases with age. Newborns will typically spend about 50% of their sleep in REM, while adults will usually spend around 20%.
Significance of REM Sleep and Non-REM Sleep
- REM sleep enables our brains to better process emotion, long-term memories and creative thinking.
- Non-REM sleep is essential for memory consolidation and body restoration.
- Both REM and Non-REM sleep are needed to function optimally.
Conclusion
Understanding sleep cycles and the difference between REM and Non-REM sleep is an important part of proper sleep health. We all need to ensure we get enough sleep each night and need to aim for a good balance of both REM and Non-REM sleep. This is key to feeling rested and energized the next day.