There are one or two things in life which are certain and unavoidable, one of those things is that we all need to sleep in order to be able to function properly. It is a fact that you can survive three times as long without food as you can without sleep.
As human beings we recognise the importance of a good night’s sleep. We recognise the importance and we acknowledge how much better we feel after a good night’s sleep, yet often it is so elusive and hard to achieve and even appears to come bottom of the list for many people – almost an added bonus which is great if you can get it! It is true to say that modern lifestyles seem to almost disregard nature’s way of replenishing and restoring the body which is sleep.
A good place to start when talking about sleep is to establish exactly WHAT is sleep. We should not think of sleep as simply being the time when we are not awake. Sleep is so much more complex than this and falling asleep is not like switching off a light just as wakefulness cannot be likened to switching a light on! There are variations within sleep and wakefulness. Imagine how you feel during a typical day – do you really feel “wide awake” from the minute you get up to the time you go to bed? Unlikely. Chances are that you experience a whole range of feelings during the day, for example you might reach your “peak” mid-morning when you really do feel wide awake to feeling rather weary mid-afternoon and a whole host of other feelings in-between.
So just as you are not always wide awake when you are awake, neither are you always fast asleep when you are sleeping! Sleep is part of your life – it is not a simple or passive state but a period when your body performs absolutely vital activities. Sleep is not an inactive process so do not think of it as separate from the rest of your life but rather a part of our life which is not in the waking world. What is more, it is a most intriguing, fascinating and mysterious part of our lives.
Sleep is active because it is when we are asleep that our body tissue is repaired; proteins are laid down during sleep and some hormones – such as the growth hormone in developing infants and children – are produced selectively during sleep. These are just a couple of the physical processes taking place while we are asleep. There are also very important mental and emotional processes which require sleep. Some of the most noticeable effects of lack of sleep is inattention, disorientation and memory problems and for our emotional function you will notice irritability, feeling over anxious or excitable or sometimes feeling rather depressed after a period of little or poor sleep.
The famous Israeli scientist, Dr Peretz Lavie wrote a semi-autobiographical book published in 1996 about his experiences in sleep research called “The Enchanted World of Sleep”. This is a wonderful title which really describes the richness, diversity and preciousness of sleep which remains so mysterious.
Who wouldn’t love to find out exactly what goes on in our lives within sleep?
By studying brain activity during sleep laboratory recordings, research studies show that sleep is a very complex yet very ordered process. It is made up of different sub-types and stages which are organised in a series of cycles repeated throughout the night.
Sleep is measured by taking three types of measurement, namely:
EEG standing for electro-encephalography whereby EEG signals are different when you are asleep to when you are awake. EEG is also used to measure the different stages of sleep.
EMG standing for electromyography which measures muscle activity because muscle tone also differs when you are awake to when you are asleep and again at different stages of sleep.
EOG standing for electro-oculography which measures eye movements during sleep thereby identifying dreaming sleep as our eyeballs make characteristic movements telling us when someone is in this stage of sleep.
Habitual sleeplessness or insomnia is a common disorder although sometimes it seems that an individual who claims to suffer from Insomnia is actually getting more sleep than even they may realise! I am sure that most of us at some time or another have uttered the words “I didn’t sleep a wink” but there are clearly differences in the way people perceive sleep.
Obviously when we first go to bed our desire and drive for sleep is stronger than it will be later on and explains why sometimes we feel refreshed and awake after only a couple of hours sleep or after a short nap. People who suffer from Insomnia should definitely avoid taking a nap as this will potentially diminish your body’s drive for sleep when you go to bed at night.
It is interesting to think about your sleep patterns. The longer you are awake, the more your body craves sleep so you could say that wakefulness increases the sleep drive and sleep reduces the body’s drive for sleep. There is a very clever analogy put forward by Dr William C Dement of Stanford University, California which I like very much and goes something like this: with each hour that we spend awake we accumulate an increasing “sleep debt”. In healthy, good sleepers this debt is repaid in full by the night’s sleep and they awaken refreshed and back “in balance” the next morning. Some individuals through lifestyle choices or other reasons find themselves in a state of chronic “sleep debt”.