I'm sure you have heard the phrase "sleep on it" many times. Likewise I expect you have had the experience of going to bed with a problem only to wake up with the solution. How does sleep present us with answers? Why is it so important?
Up until the 1950s scientists generally assumed the brain was shut down while we slept. The latest research however tells us that while we are slumbering our brain is busy processing information gathered during the day.
A German psychologist had evidence as far back as 1885 to suggest that sleep protects simple memories. In 1953 Eugene Aserinsky and Nathaniel Kleitman of the University of Chicago discovered variations in the brain activity of sleeping people. They found that sleep follows a 90 minute cycle that takes us in and out of rapid eye movement (REM) Decades on it was discovered that in between these REM phases, during slow wave sleep, collections of neurons were independently firing. With large collections of brain cells firing in synch, it became clear that the brain was not merely idle at all.
In 1994 a ground breaking study became a turning point in our understanding of sleep. At the Weizmen Institute of Science in Israel, neurobioligists Avi Karni, Dov Sagi and colleagues demonstrated that when volunteers had a good night sleep they improved at tasks involving rapid discrimination between objects. This was the case ONLY if the volunteers had had a normal amount of REM sleep.
The different stages of sleep
Sleep is divided into five distinct phases, each defined by specific brainwaves that can be measured through EEG. Fig. 1 below shows these stages and the amount we should get of each when we sleep. I have also included the distinguishing brainwaves and characteristics of each phase.

Stages 3 & 4 merge together and are the periods we experience the most slow wave (delta wave) sleep. Slow wave sleep is needed to recuperate used up energy. Studies have found that if deprived of sleep then the rebound back into slow wave sleep is faster because the body has a need for more. Now stage 5 is different, REM (beta wave) sleep actually burns up energy and serves an altogether different purpose. The brainwave examples in Fig. 2 below clearly show the brain is highly active during a beta REM phase.

REM and mental health
In terms of mental health REM is extremely important. Each and every day we face different situations and circumstances. Inevitably some of these may be the cause of stress and emotional arousal. Of course these levels of stress will vary depending on a number of factors. The most important being the thoughts patterns surrounding the events. The link between negative thinking and anxiety is well known. This emotional arousal needs to be managed so it doesn’t adversely impact on the next day or continue increasing until it leads to further anxiety related issues or depression. The brain has a coping mechanism for dealing with these levels of emotional arousal. You guessed it! REM is that mechanism. During REM sleep the brain reruns the day’s events in formed memories, reviewing and stabilising them so that they are of more use to us. Our unconscious mind can analyse these memory collections and identify what content is important or helpful to us and what can fade away. The brain solves problems and dispels accumulated emotional arousal in this way. So when REM sleep is working as it should we wake up feeling free from the upsets of the previous day. This means we can cope better with any new challenges we face.
We know REM takes up around 20% of sleep when it is working as it should and it is important that we get the right amount. Too little REM sleep would mean that there is a risk of ending up with a surplus of anxiety that has not been dealt with only accumulated. Too much REM is also counterproductive as it uses up an enormous amount of energy.If there is too much emotional arousal during the day caused by negative thinking or circumstance, REM sleep will work overtime to cope with it. Likewise oversleeping could lead to too much REM. Both negative thinking and oversleeping are characteristics of depression and because they lead to an increased amount of REM, the person often feels exhausted when they wake up and/or lethargic throughout the day.
Getting a good night’s sleep
A person can feel dramatically better just by getting their sleep pattern in order. In today’s modern world people are generally getting less sleep than they should be. Even with a fast paced lifestyle sleep should be seen as an important part of health.
• Develop a routine. Go to bed at the same time and wake up at the same time. An adult should sleep around the 8 hour mark.
• Avoid eating a heavy meal with less than 2 hours before bed
• Avoid any stimulants at night that may keep you awake (coffee, chocolate)
• Unwind in the evenings. Try to relax and not think of the days problems. A warm bath or relaxing music may help. If you are anxious try relaxation techniques, hypnotherapy (suitable CD) or meditation.
• Get regular exercise
If anxiety or stress consistently stop you from sleeping, you should consider seeing a qualified therapist or your GP. Playing a hypnotherapy CD as you go to bed at night will reduce your general anxiety levels and help you get a good night’s rest.
