There are many impressive processes within the brain and one of them is the circadian rhythm.
The circadian rhythm is essentially your body clock. Your 24-hour cycle that tells you when to sleep, get up in the morning, and eat.
Yes, your body has a clock
Do you naturally wake up in the morning? Or is it more a sudden jolt after your alarm brings you to life? If it’s more a natural process then this is your internal clock at work.
Interestingly it can be pre-programmed - you’ll have done this many times. Waking up before your alarm goes off, for example. Your body clock can be so accurate that you can wake up 1 minute or even seconds before it is due to go off.
Jet lag is an example of what happens when you disrupt the internal clock. Your entire body struggles to adapt, affecting your ability to concentrate, eat, rest and sleep.
Circadian rhythms exist in all living organisms, including plants. The external stimulus is natural light. However even without light, the 24-hour cycle will continue.
Why is this important for studying?
One of the reasons for going into detail is to show how relatively small changes in your behaviour e.g. studying late into the night, can have a significant impact on your ability to function. In this context - your ability to concentrate and remember.
Pulling an ‘all-nighter’ to prepare for an exam is a badge of honour many students wear with pride. It’s seen as a measure of how committed and mentally tough you are. On one level the effort and difficulty of that task is impressive,
but given that exams are a test of cognitive ability anything that reduces your chances of doing well should be avoided.
If Usain Bolt was to beat his own 100 meters record after a night ‘out on the town’, only having two hours sleep, he’d be a hero. But if he lost, he’d be criticised. So why would someone who had invested so much of their time put
that at risk?
In simple terms you need to help your brain perform at its best.
Rhythms and memory
Here’s a little more technical detail to illustrate a simple point.
If you don’t follow your natural sleep patterns, your ability to memorise and retain information will be affected.
Retention appears to hinge on the amount of a neurochemical you have (GABA), which inhibits brain activity. And it is the Circadian clock that moderates the amount of GABA produced.
For instance, in an experiment, using hamsters, where the circadian clock was effectively disabled the hamsters were unable to remember anything.
Look after yourself
There is a far more detrimental side to the disruption in your circadian rhythm. Research has identified* a direct link with mental health disorders such as depression.
This is of particular interest given the rise in reported levels of depression amongst students. One area that’s being investigated is screen time: be that from mobile phones or computers. The artificial blue light emitted from these devices could
well be confusing your circadian clock.
Why we sleep is still uncertain, but it’s believed that deep sleep helps the brain consolidate all the experiences from the day, including what is learned.
When you go to shut down your computer, it may say “sleep mode - do not turn off during this update” – that sounds like good advice.
The Learn Better blog is a series of evidence based stories from the world of education, with a common theme - to inspire and motivate students. They are mostly based on original articles/blogs by Kaplan's Head of Learning, Stuart Pedley-Smith.
For further information, there are also a number of organisations that provide advice on
getting better sleep.
*https://www.health.harvard.edu/newsletter_article/sleep-and-mental-health