How can we help students prepare for exams more effectively?
This is the second in a series of three blogs aimed at teachers, pupils and parents to be exam ready. This post looks at the importance of sleep drawing on scientific research and best practice.
Recent advancements in sleep science have proven what many of us have suspected all along: lack of sleep is bad for humans in pretty much every way we can imagine, but when it comes to preparing children for exams, it’s especially detrimental to their memories and emotions. Sleep needs to be well-managed if we are to be successful. Considering how important it is, it’s surprising that research into sleep is still a relatively new field. As with a lot of brain-related science, a lot remains a mystery, but advances in technology is helping to fill in many of the blanks.
‘8 hours a night’
Everyone knows ‘8 hours a night’ is the amount of sleep we should aim for, although recommendations from a recent two-year study increased this to 8-10 for teenagers. Merely worrying about not getting enough sleep is the best way to guarantee that we won’t get anywhere near 8 hours a night. We first need to understand a couple of things about how we sleep.
The rhythm of the night
Sleep is regulated by two things. The first of these, our circadian rhythm, is our body clock and it changes slightly throughout our lives. Adults run about an hour earlier than teenagers. So please be reassured that you are not just feeling worn out. Going to bed sooner is just part and parcel of being an adult! For teenagers, most of their deep sleep occurs in the 11 PM -3 AM window of their circadian rhythm. Deep sleep is essential for memory formation. It transfers information from our short-term store (the hippocampus) to long-term memory (the cortex). Without enough sleep, our short-term memories simply become overloaded and we can’t take on-board new information.
The power of dreams
Arguably, even worse than the toll on memory is the price a teenager pays if they miss out on the dream phase of sleep. Between 3 AM and 7 AM is the time when they dream. Recent experiments have indicated that one of the main functions of dreams is to keep our emotions in check. If you’ve ever woken up the day after something unpleasant has happened to you and thought ‘well that wasn’t so bad in hindsight was it?’ you have your dreams to thank.
If we skip the second half of our circadian rhythm we are infinitely more fractious and less resilient the following day. And the last thing we want teenagers to be during an exam period is even more fractious than usual.
Feels like jet lag?
Circadian rhythms are determined by the sun. That’s why we get jet-lag. Humans are not built to travel that quickly around the planet. If we’re plunged into darkness several hours before we’re accustomed to, or introduced to sunrise when our brain thinks it’s sunset, then we shouldn’t be surprised when we find ourselves wide awake at 3 AM on the other side of the world. This is an extreme example, but if you know a teenager who has trouble staying awake long enough to study, it could be because they are spending too long cooped up inside in the afternoon. Nudge them by suggesting a walk to the shops.
Don’t look into the light!
The worst thing a child can do in the run-up to bedtime is to keep their phones or other electronic devices within reach of their beds. Exposure to any kind of light will mimic the effect of the sun. TVs and computer screens aren’t good, but the blue light from phones and tablets is the worst. No one should have notifications going off in the middle of the night but some teenagers struggle with turning on the ‘do not disturb’ mode. If they do, nudge them into putting the phone on charge in a different part of their room, out of physical reach. And definitely switch off any pings, beeps or vibrations.
More bad news for caffeine
The second thing we need to know about sleep is adenosine. This is the chemical which actually sends us to sleep. It builds up inside us from the moment we wake until the moment we fall to sleep. Nothing can stop this build up. Even caffeine only delays the inevitable. I explored the potential dangers of caffeine in Part 1.
What I didn’t appreciate until I started looking into sleep science is quite how damaging it is on sleep too. All caffeine manages to achieve is to block the receptors for adenosine, holding it off from being absorbed for a while. This means that when the caffeine-induced delay finally wears off, we suddenly crash into sleep mode. So, surprise, surprise – we lose any energy to do anything. The bad news for getting a good night’s rest is that caffeine has a half-life, like radioactive material. Although it takes twelve hours for caffeine to fully leave the body, half of it is still present after six hours.
As with eating and drinking, all of the advice in this blog should be instilled as habitual as soon as possible. Scientists and doctors now refer to this as ‘sleep hygiene’ and we owe it to our children, as well as ourselves, to make this a well-being priority. Under no circumstances, should anyone be drinking caffeine anywhere near their bedtime.
In Part 3, I will be exploring how to stop children doing what they think is effective revision, but is really just procrastination. You can catch up on part one here.