Text by Corina Tan
I am a night owl. I get most crucial work done at night when I can focus better. I love the quiet and peaceful environment, when the rest of the world is fast asleep. It seems to promote a sense of calm and tranquillity that is absent from daytime. However, I also understand the importance of sufficient sleep and have struggled with this from a very young age.
Sleep is something that we all consciously know is good for us. Some people enjoy sleeping more than others and take a quick shut eye whenever they can, while others prefer to maximise all hours of the day getting all their chores done, squeezing in as much work as possible and leaving sleep last on the list. Prioritising good quality sleep is actually more important that we realise. It isn’t just to promote general health and well-being, but it also has a very important role in regulating our emotions and impacting our mental health.
There are two types of sleep, and each effects different areas of our wellness. The first is non-REM sleep also known as deep sleep. Deep sleep is a restorative kind of sleep that helps the body recover from the day’s rigours. It is sometimes called a slow-wave sleep because brain waves slow significantly during this stage. As we go from the lightest sleep stage to the deepest, breathing and heartbeat slows down, muscles start to relax and brain waves slow down even more. By comparison, the REM (rapid eye movement) sleep helps process thoughts and create lasting memories based on the day’s experience. It is in REM sleep that we do most of our dreaming, and our heartbeat and breathing return to levels that are nearly what they are when we are awake. Our brains become very active, and eyes move back and forth rapidly beneath closed eyelids.
Throughout the night, we experience several 90-minute cycles of sleep beginning with non-REM sleep. At the start of the night, this rejuvenating phase of deep sleep takes precedence and very little REM sleep follows. However, as the night progresses the REM part of the cycle gets longer while deep sleep gets shorter. When the body is well rested and does not need as much restorative deep sleep anymore, we get more REM sleep in each cycle. This means most of our REM sleep happens in the last few hours of sleep, and most of our deep sleep happens near the start of each night.
The brain uses REM sleep and dreaming to regulate emotions and consolidate memories. This is why a full night of sleep is very important. When sleep is cut short to five hours instead of eight hours for example, that means we miss out on the bulk of our REM sleep at the end of the night. This also means we are shortchanged emotionally as we don’t get as much opportunity to regulate our emotions. REM sleep helps make sense of experiences in the waking hours of life, where dreaming helps to release unsettling and confusing emotions that are too strong. Our memories are also affected as this lack of sleep messes with the way our brain processes them.
Sleep deprivation can also have powerful effects on our mood and cause depression. To treat depression, doctors prescribe medication which inadvertently suppresses REM sleep. This results in a chicken-and-egg situation where people aren’t able to regulate their emotions with sufficient REM sleep thus leading to mood instability. This negative cycle then continues, which makes depression very difficult to resolve.
Lack of sleep on a regular basis will also cause other physical problems like cardiovascular diseases and hypertension. People have also reported getting sick easily or more often with continuous sleep deprivation. Getting sufficient hours of sleep means true and complete rest and rejuvenation of body, mind and soul as it encompasses all that’s needed to address our total wellbeing.
