“How did you sleep?” Common, yet thought-provokinguttered each morning in most countriesacross the globe. But there really is much more to it than simple courtesy.
Getting adequate sleep is vital to your health and welfare. To understand how sleep affects you, it is important to know that as you sleep, you pass through a cycle of different phases, each with its own unique qualities.
REM (rapid eye movement) sleep has been the subject of inquiry and interest for decades. What is the importance of REM sleep in your overall health, as well as in your ability to learn new things?
What is REM Sleep?
When you’re asleep, you pass through different phases of slumber. Each complete cycle lasts about 90 minutes and every phase has unique characteristics. The brain (hypothalamus, brain stem, and thalamus) is very active and involved when the human body is in sleep mode.
REM sleep, as the last phase, occurs about 90 minutes into sleep, and recurs about every 90 minutes until you awaken. Norepinephrine, serotonin and histamine which are chemicals found in the body are at lower than normal levels in REM sleep. During this phase, rapid eye movement can be observed, and brain activity is close to a wakeful state. This is the period when most dreams occur. However, during most of REM sleep, skeletal muscles are temporarily paralyzed which is a good thing or you may find yourself acting out your dreams while you’re asleep.
In fact, very small rapid movements (similar to eye movements) may sometimes be observed during this phase. Finally, just like brain activity, other biological aspects of your body also act like you might be awake. During REM sleep, the rate that your heart is beating, the rate that you are breathing, and your blood pressure are all higher than in other phases of sleep.This is what REM sleep looks like, but what is its significance?
The Purpose of REM Sleep
There has been much study into the role REM sleep plays in the human body and much has been learned, but there are still many questions. Most of the research on REM sleep has been done in observational studies, comparing what was found in different types of people with different sleep patterns. The significance of low norepinephrine, serotonin and histamine is believed to play a crucial role in the tasks of REM sleep.
Sleep, in general, gives the body time to heal and repair. It is also a time when memory consolidation occurs. In other words, learning that took place during the day can be sorted and stored in a logical fashion so that it can be retrieved later. It might be useful to take a closer look at how REM sleep keeps us healthy.
Loss of REM Sleep and Health
Norepinephrine mobilizes the body for action. It gives you that “fight or flight” feeling when you are startled or scared. Histamine, usually known for its role in allergies and inflammation, actually also helps us stay awake. Serotonin has a role in many parts of the body including mood, increasing the activity of digestion, stimulating bone growth and influencing sexual libido. With these chemicals suppressed during REM sleep, the body’s workload decreases.
A recent study found thatpeople who were deficient in REM sleep have a much higher chance of dying from cardiovascular disease, as well as many other illnesses. It is also obvious that anyone who has had interrupted sleep will be drowsy during the day, leading to careless actions and poor decisions, all dangerous to health and to well-being.
Loss of REM Sleep and Learning
It is thought that these same chemicals play a crucial role in learning. REM sleep is believed to be the time when we consolidate our memories. For learning to successfully proceed, it requires acquisition, consolidation and recall. We “acquire” new knowledge while we are awake. We obviously “recall” when are asked a question and respond. But consolidation occurs when we are asleep.
During REM sleep, our brain is able to sift through what we have taken in during the day, discard what might be unnecessary and essentially file the new information in the right place so we can retrieve it later. This is why REM sleep is thought to improve critical thinking. It is also believed to be important for visual learning and procedural memory.
How Do I Know if I’m Not Getting Enough REM Sleep?
If you have slept through the night and woke up refreshed, you most likely got adequate time in all the stages of sleep. However, there are a few things you can look for if you’re worried that you’re not getting enough REM sleep — foggy or groggy in the morning, lacking in energy during the day, feeling hungry often or gaining weight, don’t feel like exercising, being forgetful,and irritable. Some things you can try in order to get sufficient REM sleep is to avoidalcohol, get plenty of exercise, make your sleep space peaceful without a lot of stimulation and stick to a nighttime routine. If you’re still suffering after trying these tips, it is time to talk to a sleep specialist.
If you are having trouble sleeping, or experiencing sleepiness during the day or any other signs that you may not be getting adequate sleep, then Dr. Joseph N. Gabriel and our experienced staff at SC Internal Medicine Associates and Rehabilitation are here for you. We want to help you get the sleep you need. To make an appointment for sleep or any of your healthcare needs, please call us at (803) 749-1111, or request an appointment online.
