We spend about a third of our life sleeping. Sleep is a daily recurring state in which your body and mind take a break. It is important for growth and for your memory. Your body recovers, your muscles relax and your memories are stored. You are getting ready for a new day.
The quality of sleep is linked to how we function during the day. Not sleeping or sleeping very little seems to strongly affect how our brain works. It affects our memory, ability to concentrate, our speech, our response time, decisiveness and our sense of time, space and planning. And it also affects our emotions and physical health. Sleeping badly and not long enough may have a negative impact on, for example, our mood and perseverance and good sleep ensures that we get more energy and a fitter body.
Sleep is a complex process in the brain which is affected by lots of internal and external factors. The entire sleep process, from going to bed to getting up, can be divided in four phases:
1. The preparation
2. Falling asleep
4. Waking up
Yawning, burning and heavy eyelids - these are clear symptoms that you are getting tired. It is how your body tells you, after a period of mental and physical activity, that it needs rest.
We slowly become less aware of our surroundings. A distinctive characteristic is that quick eye movements switch to slow, rolling movements. When we fall asleep our body temperature decreases. To make this happen our body releases water (transpiration) which evaporates on the skin. That is why adequate ventilation of your bedroom, mattress and bed is important.
Sleep itself consists of several cycles After each cycle there is a transition stage, during which we wake up momentarily. On average we wake up about seven to ten times every night, usually without being aware of it.
Within each cycle of about 1.5 hours, you go through the following 3 phases:
In the early morning hours proportionally less deep sleep phases occur, allowing for the transition to waking up to take place more gradually. When you wake up, your body temperature rises. Your body does this, as if your biological clock were switching on the heating.