As we grow older, work commitments, travel schedules, even our social lives make this an almost inevitable fact of life. This is bad news in so many ways.
Over the last century, the number of hours an average adult sleeps has been reduced significantly. A century ago 8-9 hours of sleep per night were considered the norm. Even in the 1980s the average adult was expecting to sleep between 7-8 hours. In our decade, however, this is further reduced - we now expect, on average, between 6-7 hours of sleep a night on weekdays.
Many of us manage to add a couple more hours to this at the weekends, if we do not have children. This, however, does not make up sufficiently for the shortfall. The implications for both our bodies and our brains are manifold. We all “know” in theory that this is not a great thing to do, but do we actually know why?
We may have read that lack of sleep, or “sufficient sleep,” is often implicated in air disasters, car crashes, even the Three Mile Island nuclear power accident. It is clear that when we do not sleep regularly and enough the functioning of our bodies as regulated by our minds is reduced. What we may not know is that our actual IQ levels drop commensurate with the amount of sleep reduction.
An hour of sleep less per night causes only a 1 or 2 point reduction in IQ, but cumulative sleep deprivation can effect an IQ reduction of as much as 15 points; reducing an intelligent person to robotic thinking. This then manifests itself as the “automatic pilot” we often refer to when we have set off to the shops, only to find ourselves en route to work instead.
The reasons behind this are shockingly simple. In a nutshell: one of the theories, held for centuries, was that sleep was when the human brain “recovered” from its exertions of the day. This was the time when it zoned out, calmed down, preparing itself for the onslaught of the fresh day ahead. With the advancement of brain imaging techniques, however, it has become clear that the reverse is, in fact, the case. Our brains are at their most active during the hours of sleep, with neurons firing electrical commands to one another in a constantly changing firework of patterns – showing, in fact, far more furious rhythmical activity during sleep than when we are awake. This is the time that our brains perform what is arguably the most vital of their functions.
During sleep, our brains - crudely put – sort our memories and categorise them. These memories are then stored. This process is repeated over and over at a furious speed, until memories are firmly stored in such a way that they can be retrieved by the individual at will. Consolidation and understanding of a day’s learning is done – literally – during sleep.
If this process is disturbed, whether temporarily (by travel across time-zones, for instance) or regularly (by shift work or irregular hours – for example during exam revision), the work of the brain, in its categorising and storing, is disturbed; the learning process is interrupted, the steps necessary to fulfil this function are only partially completed.
When this happens retrieval of information learnt becomes patchy or impossible, connections fail to be made and some of the “bigger picture” and sense is lost. The implications of this for learning in any context are enormous. There is a copious amount of evidence to support the claim that a healthy and consistent amount of sleep enables, indeed boosts, learning, especially of certain tasks. Many famous experiments have been conducted to check these claims and the findings were repeated: if two groups were given the same data and asked to work out a problem related to this, the group who were allowed sleep within the interim time outperformed the control group 3:1.
Lack of sleep clearly affects learning and reasoning negatively. Sleep loss leads to a loss of brain function and cancels out the added benefit of “sleeping on” a problem. Sleep loss affects attention, short-term and long-term memory, day-to-day functioning, reasoning ability, mathematical knowledge and many more vital mental functions adversely. The only possible conclusion from this is: Do Not Cut Down On Sleep.
More importantly and urgently: Do not allow your children/yourself to cut down on the amount of sleep before exams. Sleeping less to have more time to revise subjects achieves the opposite result: You will remember less of anything learnt despite having spent additional time on revising.
In order to ensure optimal performance during exams, teenagers and young adults:
1. Must try to achieve a regular amount of sleep. (Individual needs vary, but a minimum of 8 hours of sleep each night is definitely advised.)
2. Must try to keep to a predictable schedule, even at weekends and during holidays. While sleeping a little longer when possible may have some benefit, sticking to a regular schedule – even over the weekends - is the most beneficial.
3. Must sleep in a quiet, darkened room, free from electronically emitted sounds and lights.
4. Must try to ensure that if mobile phones are being used as alarm clocks, no other sounds or lights are going to be emitted by these and that all further electronic devices are turned off.
5. Must, just like everyone else, start winding down towards rest and sleep a good half hour before actually getting into bed. A shower is ideal for this; doing a workout or watching something highly emotional or fast-paced is not.
6. A drink of milk and a small snack may help; a heavy, last-minute meal with a fizzy drink does not.
7. Must steer clear of drinks containing caffeine from mid-afternoon onwards no matter what they believe. This means no Coke, Pepsi, Red Bull or coffee should be consumed. If sleep alone were enough to ensure academic success, teenagers would be the most academically successful amongst us. Sadly for them, this is not the case. But the fact that sufficient and regular amounts of sleep, coupled with hard work and dedication, contribute to more favourable academic results cannot be disputed.
– xx –
Agnes Holly has worked for more than 25 years in education ranging from university to nursery, and everything in-between. She is a qualified SEN teacher and has worked extensively with children who have dyslexia and ADHD. She has additional practical experience in the form of five of her own children aged between 6 and 23.