It is characterized by thought-like mental activity and little to no eye movement.
Sleep is divided into four stages.
Approximately 75% to 80% of sleep is spent in NREM sleep.
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The first full NREM-REM sleep cycle is typically shorter, lasting around 70 to 100 minutes.
Subsequent cycles last around 90 to 120 minutes.Most people go through four to six sleep cycles each night.
Signs of NREM Sleep
The body goes through many changes throughout NREM sleep.
Types of NREM Sleep
There are three stages of NREM sleep.
Each stage of NREM sleep serves a unique purpose and plays an important role in supporting brain health.
During stage 1, brain waves begin to slow.
Breathing, heartbeat, and body movements are also slow.
While muscles become more relaxed, you may also experience periodic twitches or jerks.
Stage one is the briefest stage of sleep, lasting just five to 10 minutes.
While activity is slowing at this point, the brain is still fairly active.
NREM Stage 2
The second stage of sleep is characterized by slowed body activity and decreased awareness.
During this stage:
During stage two, the brain produces two distinct patterns of brain waves.
Sleep spindles are short spikes in brain activity.
K-complexes are sharp bursts of electrical activity followed by a brief dip in activity.
Stage 2 NREM sleep accounts for approximately 50% of all time spent sleeping.
Stage 3
The third stage of NREM sleep is also the deepest.
It is marked by the emergence of large, low-frequencydelta wavesand even slower activity known as slow oscillations.
It is vital to get enough stage 3 NREM sleep each night.
This punch in of sleep causes people to feel refreshed and well-rested the next day.
Memory Consolidation
Memory consolidation occurs durion NREM sleep, which is critical to learning.
Slow-wave sleep naturally declines with age, dropping more than 60% between the ages of 10 and 20.
Your sleep needs vary depending on your age.
Sleep needs also tend to decline as people age, which is why children require more sleep than adults.
If you think you might be experiencing a sleep disorder, talk to your doctor.
A diagnosis and treatment plan can help you get the restful sleep you need.
Recap
The bottom line is that NREMsleep is essential for mental and physical health.
If you think you might be suffering from a sleep disorder, talk to your doctor for help.
A soothing bedtime routine can help signal to your body that it’s time to sleep.
This might include taking a warm bath, reading a book, or stretching.
Yoga, for example, may help promote improved sleep quality.
This can help promote relaxation and make it easier to fall asleep.
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