Today, Americans sleep two hours less than a century ago, and the impact it has on their health is considerable
It’s not only electric lights – computers, mobile phones and television are causing havoc to our sleeping patterns. Yet in high achieving Western countries sleeping is often seen as an inconvenience. It gets in the way of getting things done, so we feed a multi billion dollar stimulant industry to keep us alert
As early as 250 BC, the Greek philosopher Aristotle was questioning the role sleep played in our lives, and the American Thomas Edison, who discovered electricity, was convinced that sleeping was a bad habit which would eventually be overcome. Ironically, modern technology, which is largely to blame for the increase in insomnia, can also be credited for giving us an insight into the vital role sleep plays in our survival.
Every living creature on earth, from jellyfish to humans, needs a daily period of rest which follows the circadian cycle of day and night.
Certain species though seem to have adapted better than others. Dolphins, for instance, are able to rest one brain hemisphere at a time. This allows them to keep swimming while asleep. Many birds can also sleep while they are flying.
However, humans haven’t evolved such skills and recent research has shown that long term disruption of our natural sleep pattern brings an increased risk of diabetes, heart disease and can even trigger the onset of dementia.
According to the American neuroscientist Dr Steven Lockley, “Sleep might be more important than food, as animals will die of lack of sleep before starvation.”
Anyone who sleeps less than six hours a night has an increased risk of depression, psychosis, and stroke. We have also discovered that lack of sleep can cause obesity because we need adequate sleep to overcome the hunger hormone ghrelin, which stimulates us to eat more than we should.
Even small changes in our sleep pattern can have major repercussions. It has been reported that the day after daylight saving changes in the United States, there is a 24% increase in heart attacks and a significant rise in fatal car crashes.
While we are asleep the brain reviews, edits and consolidates the information we have collected during the day. This process is very powerful, but the brain doesn’t always edit wisely.
To reduce the risk of Post Traumatic Stress Disorder (PTSD) in the army, it is now recommended that soldiers who have just been exposed to traumatic events should be kept awake for several hours on their return to allow more benign memories to implement themselves in their psyche.
Since the invention of the electroencephalogram (EEG) we have been able to record the electrical activity in the brain during our sleep. It has now established that our sleeping pattern follows several distinct stages. The first stage, which is like an introduction, is very shallow and lasts less that five minutes. Then we quickly dive deeper into unconsciousness. As we enter stage two, the brain turns inwards and the billion nerve cells called neurons start to fire more evenly. They make new connections between themselves, as they store and edit the recent memories into the cerebral cortex.
When we sleep we literally make intuitive connections we may never have consciously formed.
This probably explains why sleeping on a problem is often a good idea.
In the next stage, our brain activity slows down, our heart rate decreases and our temperature drops as we dive even deeper into stages three and four of sleep. This is the deepest level of unconsciousness, close to coma. The new memories have been edited and stored, and it is now time for the body to repair itself, so growth hormones are stimulated to heal bones, muscles and tissues. Mental activity is reduced by this stage and we might not even feel pain. We remain in stage four for only about 90 minutes.
In a normal sleeping pattern, we will experience these four different stages several times during the night, briefly waking for a few seconds without noticing between cycles. Dreaming occurs between these stages, during a short period called Rapid Eye Movement (REM) sleep.
According to the experts, not being able to remember any dreams is actually the reflection of a good night’s sleep.
REM sleep is ruled by the limbic region of the brain, which is responsible for our most basic emotional responses like sexuality, aggression, fear, love and joy.
Dreaming is akin to being in a psychotic state. During REM sleep, the brain gets a daily opportunity to express its creativity. We experience powerful hallucinations and delusions and become sexually aroused, as we temporarily shed our inhibitions to take a short walk on the wild side. It would be real shame to miss any of it.
We’ll look deeper into sleep next month in NOVA.
Olivier Lejus BHSc.MHSc. is a registered acupuncturist and Chinese herbalist practising in Sydney. A former casual university lecturer and tutor in Oriental medicine with over 15 years experience in clinical practice, Olivier specialises in Japanese- style acupuncture for the treatment of male and female infertility, migraine, pain, and insomnia.www.olejusacupuncture.com