“As far as I know, the only reason we need to sleep that is really, really solid is because we get sleepy.” William Dement – Stanford University Sleep Research Centre.
There is very little research into sleep (and even less into sleep disorders), so much so that no-one is exactly sure why we sleep. It seems such a strange thing in evolutionary terms to sleep – to deliberately leave ourselves vulnerable and defenseless to predators while we snooze and snore.
It was only in the last century that scientists realised that the brain was active during sleep, up till then it had been thought that sleep was a period of inactivity and not worth studying. Now modern tracking techniques have shown how active the brain is at night, this has lead to the discovery of the sleep cycles and the difference between REM and deep, slow wave sleep. These discoveries have allowed for new theories to be put forward as to why we sleep. However they are sill only theories!
Theory 1 – Rest and recuperation
That sleep allows the body a chance to rest and recuperate from being in a state of heightened awareness throughout the day. Sleep allows the body time to heal and repair itself. If we become sleep deprived we are more susceptible to illnesses and take longer to recover.
Theory 2 – Learning
Sleep and the temporary absence of consciousness allows the brain time to process all the information it has learnt and reorganise itself. Again sleep deprivation tests have shown that a lack of REM sleep affects your ability to perform tasks and a lack of deep sleep affects the recall of knowledge.
Theory 3 – Dreaming
Dreams seem to be a result of REM sleep, so maybe the reason we sleep is to dream?
Science is still learning a lot about the world of sleep and new research will hopefully answer our questions about sleep and dreams. In the meantime, we can help our bodies and minds by making sure we allow enough time to sleep.