How Does Our Circadian Rhythm Affect Our Daily Lives?

 by Eliza Stevens

(Wiki Commons)

We all have a powerful sculpting force of our twenty four hour clock, this is known as our circadian rhythm. Every living creature on the planet with a life span of more than several days generates this exact natural cycle. The internal twenty four hour clock within your brain communicates its daily circadian rhythm signal to every other region of your brain and every organ in your body. Our twenty four hour tempo helps us to determine when we want to be awake and when we want to be asleep, for example most of us know that when our alarm goes off for school - we want to fall back asleep! Your circadian rhythm also controls other major rhythmic patterns in your body. These include your preferences for eating and drinking, your moods and emotions, your core body temperature, your metabolic rate and the release of numerous hormones.

The twenty four hour biological clock that sits in the middle of your brain is called the suprachiasmatic nucleus.  You might assume that this is of a significant size in regard to it housing 20,000 brain cells or neurons, however it is tiny. Now I am going to tell you that the brain is composed of approximately 100 billion neurons, this now makes the suprachiasmatic nucleus miniscule in comparison to the rest of the cerebral matter. However, despite its size, it is the central conductor of life’s biological rhythm. It controls a vast array of behaviours, but most importantly when we want to be awake and when we want to be asleep.

There are three types of people, the morning larks, the night owls and a mixture of both. About 40% of the population are morning larks and naturally wake up at dawn, function optimally at this point and do not mind doing so. On the other hand we have the night owls, which is approximately 30% of the population, who are incapable of falling asleep early, no matter how hard they try, they also do not like waking up early, as they will have fallen asleep late and as a result find it hard to work effectively and efficiently at this time of day. For night owls, despite being ‘awake’, their brain remains in a more sleep like state through the early morning. If you believe that you are a night owl, the region in your brain, called the prefrontal cortex, which sits above your eyes, is known as the head office of the brain. The prefrontal cortex is in charge of high levels of thought and logical reasoning, this helps us to keep our emotions under control. 

This brings me on to talk about how our performance at work is impacted by our circadian rhythm. Standard employment schedules force owls into an unnatural sleep-wake rhythm and as a result their job performance is often far less optimal in the mornings. Not only are they not performing to their optimal performance in the morning, they are also prevented from displaying their full potential as their best work will be done in the late afternoon and early evening. Furthermore, owls are often chronically sleep deprived as they have to disrupt their rhythm in order to wake up with the larks, yet they do not have the gift that larks have to fall asleep early. 

However, although it sounds as though being a night owl is purely negative, there are some positives that come with it that larks do not possess. Firstly, night owls have been found to be more creative and are able to find alternative and original solutions to problems. Furthermore, a study conducted by the University of Leige in Belgium showed that night owls compared to morning larks had a significantly faster reaction time during the evening than the morning larks. The results show that regardless of wake times, night owls are able to sustain a sense of mental alertness for longer than those that go to bed early.

Overall, there are positives and negatives with both circadian rhythms and as a result some people will perform better at the early morning work tasks than others who will be more alert in the evening hours.