Sleep is something pretty much most of us take for granted, in fact, most of us never even think about it most of the time, but when you do start to think about it, you realise what an amazing process it is. The brain suddenly switches from being wide awake and conscious into this unusual semi-conscious state and then about eight hours later it switches back on again.
So exactly how does the brain switch from awake to asleep? Interestingly, the difference between being wide awake and fast asleep depends largely on the function of a few small areas in the brain.
When these ‘alerting areas’, as they are known, are at their most active, they inhibit activity in other areas of the brain that are in charge of putting us to sleep. The alerting areas insure that we remain in a stable condition of wakefulness.
Conversely, when the ‘sleep-promoting areas’ of the brain become the most active they have the same inhibiting effect, except in reverse, as the alerting areas, ensuring we have a stable and sustained sleep.
There are several keys that tell which area to inhibit the other. The major one is our own body clock, which is why you can change your sleep cycles over a long period through gradual changes. There are a number of chemical changes that occur in both areas that indicate which needs to inhibit the other and it is often an imbalance in these chemical levels which can cause sleeping problems.