Table of ContentsView AllTable of ContentsSignsTypesImpactImpact of Disrupted NREM SleepChallengesImproving NREM Sleep
Table of ContentsView All
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Table of Contents
Signs
Types
Impact
Impact of Disrupted NREM Sleep
Challenges
Improving NREM Sleep
Close
Sleep is divided into four stages. The first three stages are part of NREM sleep, and the fourth stage is REM sleep, during which rapid eye movement occurs.
Approximately 75% to 80% of sleep is spent in NREM sleep. 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
While the three stages that occur during non-REM sleep share common features, each includes distinct events and characteristics.
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.
NREM Stage 1
The first stage of NREM sleep acts as a transition between wakefulness and the deeper stages of sleep. 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. If you are awakened during stage 1, you may feel as if you weren’t really asleep at all—which is why this stage is sometimes referred to as feel like a period of relaxed wakefulness. While activity is slowing at this point, the brain is still fairly active.
NREM Stage 2
Both sleep spindles and k-complexes are believed to play an essential role inmemory consolidation, which involves processing the memories and information people acquire during the day.
Stage 2 NREM sleep accounts for approximately 50% of all time spent sleeping.
Stage 3
Stage 3 sleep is adeep sleepessential for consolidating certain types of memories, mainly declarative ones. These are memories of specific facts and events, such as things that you personally experienced and information that you have learned.
It is vital to get enough stage 3 NREM sleep each night. This type of sleep causes people to feel refreshed and well-rested the next day.
NREM Sleep Sequence
Impact of NREM Sleep
NREM sleep serves several essential physical and mental functions. In addition to aiding in memory consolidation,the body builds bones, repairs muscle, regenerates tissues, and boosts the immune system during this time, particularly during the period of deep sleep that occurs in stage 3.
Memory Consolidation
Memory consolidation occurs durion NREM sleep, which is critical to learning. This period of sleep has been shown to affect bothprocedural memory(which involves skills and the ability to learn new tasks) and declarative memory (which is the memory for facts and information).
Research has shown that specific brain patterns that occur during NREM lead to a variety of cognitive improvements, including better motor learning, word retrieval, working memory, and verbal fluency.
Evidence also indicates that age-related problems with NREM sleep can play a part in memory problems that are associated with the aging process. Slow-wave sleep naturally declines with age, dropping more than 60% between the ages of 10 and 20.
Repair, Restoration, and Growth
NREM sleep is believed to play an essential role in physical growth and repair of body tissues. Research has shown, for example, that blood pressure drops during slow-wave sleep, which can play an important part in lowering the risk of cardiovascular disease.
People with sleep conditions that prevent these nightly drops in blood pressure, such as insomnia and sleep apnea, have a higher risk, for heart disease.
Consequences of Disrupted NREM Sleep
Interruptions to the normal sleep cycle can have a variety of mental and physical health effects. Some problems that may emerge if the sleep cycle is disrupted include:
Challenges Affecting NREM Sleep
Getting enough sleepeach night is vital for short- and long-term health. Your sleep needs vary depending on your age.
According to the American Academy of Sleep Medicine, adults over 18 need a minimum of 7 hours of sleep per night. Sleep needs also tend to decline as people age, which is why children require more sleep than adults.
Unfortunately, many factors can interfere with NREM sleep, including:
Making sure you get enough sleep each night is crucial for maintaining your health. 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.
RecapThe bottom line is that NREMsleep is essential for mental and physical health. Disruptions to the normal sleep cycle can have a variety of negative consequences, so it’s important to make sure you get enough restful sleep each night. If you think you might be suffering from a sleep disorder, talk to your doctor for help.
Recap
The bottom line is that NREMsleep is essential for mental and physical health. Disruptions to the normal sleep cycle can have a variety of negative consequences, so it’s important to make sure you get enough restful sleep each night. If you think you might be suffering from a sleep disorder, talk to your doctor for help.
Tips for Improving NREM Sleep
Fortunately, there are steps you can take to protect your NREM sleep.
Stay Physically Active
Exercise is important for overall health, and it can also help improve the quality of your sleep.Just be sure to avoid working out too close to bedtime, as this might actually make it harder to fall asleep
Create a Relaxing Bedtime Routine
Preparing for sleep should be an opportunity to wind down and relax. 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.
Limit Caffeine and Alcohol Intake
Both caffeine and alcohol can disrupt sleep, so it’s best to avoid them in the hours before bedtime. Caffeine can stay in your system for up to 8 hours, so it’s especially important to limit intake in the afternoon and evening.
Create a Sleep-Friendly Environment
Your bedroom should be a dark, quiet, and cool place to sleep. This can help promote relaxation and make it easier to fall asleep.
Go to Bed and Wake at the Same Time
Establishing a regular sleep schedule can be helpful for people with insomnia. Going to bed and waking up at the same time each day can help regulate your body’s natural sleep-wake cycle and make it easier to fall asleep and stay asleep.
Use Good Sleep Habits
Avoid Blue Light at Bedtime
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