The study of sleep is an incredibly broad field that includes circadian rhythms, sleep cycles, sleep stages, and sleep disorders. Researchers and scientists are still discovering new information related to this important field, so it goes without saying that we don’t have all the answers yet. However, when it comes to the aspects of the study of sleep that pertain to our day-to-day lives, we know enough to understand their impact and what we should do to optimise some of the functions in our bodies.
In this article, we’ll discuss different topics of sleep study, such as sleep disorders and the circadian rhythm, in the hopes of making it easily accessible to anyone who is curious about the topic. At the end of our article, we included our best tips on how to maintain a healthy sleeping pattern and improve your quality of sleep.
Now that we’ve provided a brief overview of what’s to come, let’s first see what the scientific word for sleep is, and define some other important sleep-related terms.
Is There a Scientific Word for Sleep?
While there isn’t a fancy Latin word to describe the state of being asleep, there are some terms that you should be aware of when it comes to sleeping. Before we delve into the study of sleep and what happens when we sleep, we have provided a short glossary for the most important terms regarding sleep.
Atonia: refers to the REM stage of sleep, when the muscles of our body are completely paralysed.
Blue light: the light emitted from electric devices that can be detrimental to our sleep quality.
Circadian rhythm: the body’s 24-hour internal clock that controls the main functions of our body, such as sleeping and eating.
Central sleep apnea: a sleep disorder in which the brain doesn’t send a signal to our body to breathe.
Deep sleep: a stage of sleeping characterised by slowed breathing and a slower heart rate.
Dreams: images and feelings we experience when we sleep.
Insomnia: a sleep disorder in which the person has trouble falling asleep at night, or staying asleep.
Light therapy: a kind of therapy used to treat some sleeping disorders that includes exposure to extremely bright lights.
Lucid dreaming: a type of dream where the person is conscious of the fact that they’re dreaming.
Multiple sleep latency test (MSLT): a test that helps assess the speed of falling asleep.
Melatonin: the sleeping hormone that’s produced by our body to regulate our sleep.
Non-rapid eye movement sleep (NREM): the type of sleep that includes the first three stages of sleep, characterised by certain changes in our body, such as a decreased heart rate and brain activity.
Rapid eye movement sleep (REM): the last stage of sleep when we experience dreams and certain changes in our body, such as muscle paralysis.
Sleep pattern: our unique schedule that includes the time we go to bed and the time we wake up.
Total sleep time: the sum of the hours we are asleep that includes all four stages of sleep.
Why Do We Sleep?
A large part of the science of sleep is still unknown to us, but what we are sure of is that there are several reasons why our bodies need regular sleep.
The most obvious reason is an increase in energy. Sleep gives us sufficient energy to function during the day and optimise our tasks.
Another reason why we sleep has to do with our emotional and mental health. Our emotions are regulated while we sleep, which explains why we wake up groggy and irritable after not getting as much sleep as we needed.
Sleep also contributes to a healthy weight and metabolism because it controls your hunger hormones, leptin and ghrelin. You might have noticed the change in your hunger levels when you don’t get enough sleep – lack of sleep increases our hunger hormone and thus increases our appetite.
Last but not least, sleep directly affects our physical health. Sleep deprivation leads to increased blood pressure, which is a cause for heart disease. Scientists have observed a direct link between failing to get enough sleep and an increased risk of various heart diseases.
What Happens to Our Bodies When We Fall Asleep?
We went over some of the most important terms you should be aware of regarding sleep, so now it’s time to delve into the actual science of sleep. We’ll start off by discussing the four stages of sleep and what happens to our bodies when we go through those stages.
The Stages of Sleep
As we already mentioned, the first three stages of sleep belong to non-REM sleep. The four stages combined form one sleeping cycle. We go through several of these sleeping cycles every day, and the duration of the REM sleep increases with each cycle. Sleep stages are crucial because they allow the body to rejuvenate and grow, and they regulate important emotional and cognitive functions, such as memory storage. Many things can result in the interruption of one sleeping cycle, the most common of which are sleep disorders.
The first non-REM sleeping stage usually lasts from one to five minutes and it occurs when we start to doze off. We’re most vulnerable to being woken up during this stage, and our awareness of the surroundings is increased. In terms of our body, the activity in our brain starts to slow down and we experience muscle twitches at random intervals. If we aren’t woken up at this stage, we continue to stage two of non-REM sleep.
The second stage of non-REM sleep is characterised by much deeper sleep as compared to the first stage. This stage can last anywhere from 10 to 25 minutes, depending on the sleep cycle. We experience some changes in our body, such as a drop in temperature, slowed brain activity and breathing, and our muscles become more and more relaxed. It’s harder to be woken up from this stage as compared to stage 1.
The third and final stage of non-REM sleep is when we experience deeper, undisturbed sleep. Our body relaxes even further and our bodily processes like breathing and heart rate continue to decrease. We spend approximately 30 minutes in this stage of sleep. Some people even dream during the third stage, but the dreams aren’t as vivid as they are in the REM stage.
What Happens During the REM Stage of Sleep?
REM sleep is where vital cognitive functions occur, such as storing memories and learning. During this stage, our brain filters out the memories and images we’ve gathered throughout the day and decides which ones are worth keeping. We dream during this stage, and experts believe it’s crucial for creativity. In terms of our body, the muscles experience temporary paralysis and our eyes start moving extremely rapidly. If you’ve ever watched someone asleep during this stage, you would’ve noticed how quickly their eyes twitch, which is where this stage gets its name from. The duration of the REM stage increases as the night goes on – the first one only lasts for a couple of minutes, whereas the latter ones are quite longer.
Several factors affect our sleeping stages and, ultimately, our sleeping cycle. Not only can they look different from night to night, but they also depend on our age. Infants and toddlers spend a lot longer in the REM stage of sleep than elders. Plus, they’re more likely to entirely skip some of the previous stages and enter the REM stage directly. Children’s sleeping pattern looks similar to that of adults, and the time during REM decreases as we get older.
There are other factors that influence our sleeping cycles. Alcohol and medication can have a severe impact on REM activity and can decrease our quality of sleep, especially if we drink alcohol before going to bed. Certain types of medication also have this effect on our sleeping cycles, so consult your doctor if you suspect that your medication negatively impacts your sleep.
Any disruption in our sleep, such as all-nighters or daytime naps, can also result in a change in our sleeping cycle.
Needless to say, sleeping disorders also have a major impact on our sleep cycles because they make us vulnerable to being woken up in the middle of the night.
A large part of the study of sleep is examining sleeping disorders, their symptoms, and implications. We all know that sleep is crucial for our overall health, so it comes as no surprise that many scientists have dedicated themselves to the study of sleep disorders and the kind of impact they have on our sleep.
In this section, we will briefly go over the most common types of sleeping disorders and explain how they’re typically diagnosed.
Types of Sleeping Disorders
The most common types of sleeping disorders are the following:
Insomnia – the body’s inability to fall asleep and stay asleep.
Sleep apnea – experiencing irregular breathing throughout the night.
Narcolepsy – having trouble staying asleep, feeling really tired throughout the day, and falling asleep at random times during the day.
Restless leg syndrome – feeling a peculiar kind of discomfort in the legs that only stops when the legs are moving.
Nightmares – having unpleasant dreams throughout the night.
How Are Sleep Disorders Diagnosed?
Luckily, there are several ways sleeping disorders can be diagnosed. One of the most common ways to provide an accurate diagnosis is to have the patient undergo a polysomnography test. Also known as a sleep study, this test follows your sleeping cycles and the changes in your body while you sleep, such as the activity in your brain and the levels of oxygen in your body, to detect any oddities. It’s typically done at night and it requires the patient to stay overnight to replicate the feeling of sleeping at home.
While you sleep, a specialist monitors the most crucial changes in your body, such as your breathing, the movement of your muscles, the movement of your eyes, and your oxygen levels. After collecting this information, you will be called for an appointment where the doctor or specialist will share their findings on a possible sleeping disorder or any negative changes they have monitored.
Some sleeping disorders, such as snoring or restless leg syndrome, can be diagnosed more easily and don’t require a polysomnography test. If you suspect that you may have a sleep disorder, it’s crucial that you share your symptoms with your doctor so that they can recommend the right course of action.
One of the terms we introduced at the beginning was circadian rhythm. It’s just as important in the study of sleep as sleeping cycles, so let’s quickly go over what a circadian rhythm is and how it affects our body.
Our bodies work in a 24-hour cycle which determines our hormonal levels, our mood, and our eating habits. This cycle is called a circadian rhythm and it’s also found in plants and animals, so understanding how it works is crucial for our health and well-being.
There are several factors that can disturb and change our circadian rhythms, such as jet lag, late shifts, blue light, and certain mutations in our genes.
One of the ways our circadian rhythm influences sleep is by affecting melatonin – a hormone that promotes healthy sleep. When our eyes are exposed to light, our brains receive a signal that it’s time to stay alert and awake, which explains why most people stay awake during the day and sleep at night. Melatonin production starts to increase as we approach the night, and spending our nights staring at screens and using electronic devices can inhibit the production of melatonin. Electronic devices emit blue light from the screen, which sends a signal to our brain to stay awake, so we’re more likely to stay up and not get an adequate amount of sleep.
The study of circadian rhythms is fascinating. It includes close observation of how humans sleep and function, as well as comparisons between our 24-hour cycle and that of animals and plants that have similar genes to ours, such as mice.
Tips on How to Maintain a Healthy Circadian Rhythm and Sleep Better
Since you’re now aware of the importance of sleeping cycles and a healthy circadian rhythm, it’s time to share some of our best tips on how to properly maintain it so that you continue to get healthy, quality sleep.
Have a consistent sleeping routine and schedule. One of the most overlooked ways you can help your body maintain a healthy circadian rhythm is by having a consistent sleeping schedule. This includes going to bed and waking up at the same time, day in and day out. We lead chaotic and stressful lives, so we acknowledge that this is not always within the realm of possibility, but it’s important to introduce a predictable routine so that our health and sleep are optimised.
Exercise. Exercising, especially earlier in the day, is a safe and effective way to improve the quality of your sleep and your internal clock. If we remain active throughout the day and introduce a couple of quality workouts a week, the chances of us having trouble falling asleep at night will be minimised, resulting in a more consistent sleeping schedule over time.
Don’t use electronic devices in bed. As we already mentioned, the blue light that emits from screens can be detrimental to our melatonin production. To avoid a disruption in your sleeping hormones, make sure you limit your use of electronics before bed. Instead, you can try incorporating some non-disruptive activities into your bedtime routine, such as reading.
Limit your consumption of alcohol and sugar before bed. Another way our sleep cycles can be disturbed is by consuming food high in sugar before bed and alcoholic drinks. Alcohol is notorious for causing us to wake up in the middle of the night and negatively impacting our quality of sleep, whereas food high in sugar can increase our energy and cause us to stay up longer than we intended to.
Avoid caffeine after 3 pm. Just like sugar, caffeine is a stimulant that increases our energy levels. While having caffeine later in the day can be benefitial in certain situations, like studying before an exam, it could easily lead to nights where we toss and turn in bed without being able to fall asleep.
Can Someone Stay With Me During a Sleep Study?
When conducting a sleep study, the participant is usually asked to be alone in the room. However, if you have anxiety about staying alone or any other related concern, we recommend discussing it with the doctor or specialist. They might be able to accommodate you, so it’s worth a shot.
What if I Can’t Sleep During a Sleep Study?
There are several ways the doctor and specialist conducting the sleep study will help you fall asleep. If all the other methods fail, they might resort to giving you a sleeping pill that will make you fall asleep fast.
We hope you found our article on the study of sleep useful and informative.
Our body goes through four different sleep stages during the night – three non-REM stages and one REM stage, which together form a sleeping cycle. We experience several of these cycles throughout the night and the length of our REM stage of sleep decreases as we grow older. Disruptions in these sleeping stages are usually caused by sleep disorders, the most common of which are sleep apnea, restless leg syndrome, narcolepsy, and insomnia.
Another important factor in our sleep is the circadian rhythm which refers to our body’s internal 24-hour cycle that determines our hormonal levels, our digestion, and our mood. The circadian rhythm has a direct influence on melatonin – the sleep hormone that promotes quality sleep. Some of the ways you can help your body get optimal sleep include exercising earlier in the day, having a consistent sleeping schedule, and limiting your consumption of alcohol, sugar, and caffeine before bed.