We spend a third of our lives sleeping, but do any of us really understand the process? Is there any point to understanding how we sleep, or is it fine to close our eyes and drift into that sweet sleep?
The short answer is yes. Understanding sleep goes beyond knowing the benefits that come with a good night’s sleep. Just so you know, quality sleep allows you to create a good sleep schedule, it maximises your time throughout the day and most importantly, gives you the rest you need for the next day.
Sleep comes in different cycles and each one of them have distinct and particular characteristics that affect our brain activity, body temperature and many other things.
Quality sleep, unlike what most people assume, is not based on the amount of sleep you get, but rather by the degree of relaxation that both body and mind gets in a single night. Knowing the varying sleep cycles allows you to attain quality rest easier.
Studying sleep is a pretty uncommon topic, as most people tend to take sleepf for granted, especially if they rarely struggle with it. However, with the right knowledge and approach, you can increase your total sleep duration and the rest you get from it.
In order for us to gain a deeper insight on what constitutes a healthy sleep and to reap its benefits, let’s cover the different types of sleep.
Non-REM Sleep stages
Also known as non-rapid eye movement sleep, the NREM sleep cycle is divided into 3 stages, known as NREM1 to 3. Usually these stages are what we experience during the first half of the night, as they occur in intervals the moment we begin trying to sleep.
Specifically, NREM1 to NREM3 stages of sleep cover the early period of sleep where our body begins to power down and prepare for sleep. Blood pressure and other functions slows down as the sleepiness begins to take hold.
The NREM1 stage is the period where you start to doze off, characterised as light sleep where you can easily be awakened by sounds or noises. Some sleep scientists refer to this as restful wakefulness, where the body is somehow aware of the outside world.
Next up is the NREM2 stage. This is the part of this sleep cycle where your body begins to relax and loosen up. The brain exhibits signs of sleep spindles, which experts believe facilitate memory strengthening and disassociate the sleeper from outside stimuli.
Sleep spindles form at an early age, with infants 4 to 6 weeks of age already showing evidence of this occurrence, leading some to correlate it with cognitive development and maturity.
One other interesting note to consider is that as we age, our sleep patterns also adjust and in a way, mature. For example, as we get older, we actually require less sleep. .
Experts suggest that daytime napping is a contributing factor as to why this decline in sleep time occurs, among others factors like health and lifestyle.
Coincidentally, the NREM3 stage, also known as deep sleep or slow-wave sleep, is one part of the sleep cycle where ageing plays a critical factor. Studies have shown that the older we get, the less amount of time we spend in this stage.
What makes this stage different? Deep sleep is the part of sleeping where the transition to the next sleep cycle happens, which we will discuss in detail later. Scientists believe that delta waves effectively ushers in this change from light to deep sleep.
Another interesting fact about this stage is that men seem to get less hours of sleep in this cycle than women.
Deep, or slow wave sleep, is also the only part in the NREM sleep cycle that displays in a substantial manner, dreaming which is often relegated to the succeeding sleep stage.
Ask experts and they will tell you that it is good to add as part of your sleep habits the goal of reaching deep sleep as soon as you can, in order to transition easily into the REM sleep cycle, therefore spending less time in light slumber.
Rapid Eye Movement or REM Sleep
Following the deep sleep stage is the REM sleep cycle, characterised by rapid eye movements and higher chances of dreaming, brought by increased brain waves, plus incidentally higher heart rates and body temperature.
As mentioned earlier, while deep sleep may allow for some instances of dreaming, it is in REM sleep where most of our dreaming takes place, usually around 2-4 hours in a normal sleep period.
So what does it mean for our body and brain? For starters, this stage sees an increase in breathing which might even lead to sleep apnea in some cases. This is also the stage in our sleep where twitching of various muscles occur, including the face, legs, and arms, in relation with our dreams.
A person with a balanced circadian rhythm and a regular sleep-wake cycle sees a relatively undisturbed REM sleep compared to individuals who suffer from sleep problems or are having a hard time maintaining a bedtime schedule.
All in a night’s sleep
It is so important to get your full eight hours of sleep every night, as this can help strengthen our immune system and general health and wellness. Learning about sleep cycles can help improve our sleep, especially those who struggle and stay awake at night.
Understanding and familiarising ourselves with the varying sleep cycles allows us to achieve more time sleeping in the most efficient way possible.