The belief used to be that during sleep, a person would lose control of their mind and there soul would roam freely. After some research was done, that myth went away and it was said that there was no brain activity at all during sleep. With the help of modern technology, electroencephalographs or EEG’s showed that during some sleep stages the brain is just as active as when it is awake.
There are two basic types of sleep. The first is non-rem which stands for non-rapid eye movement. Non-REM is broken into four different stages. During stage one, the person has their eyes closed and are relaxed but still aware. Muscle tones and eye movement are normal. The EEG shows slow brain waves. The second stage is when you begin to fall asleep. Breathing deepens, heart rate slows down, and blood pressure falls. Stages three and four are the deepest. The brain slows down even more. If the person is waken from the fourth stage they are likely to be confused and tired for a few minutes.
The other type of sleep is REM or rapid eye movement also known as paradoxical sleep. After being in stage 4 of non-REM for about 30 to 40 minutes, you go back to stage two and begin the stage of REM. The person’s EEG looks the same as an awake and alert person. Also under their eyelids their eyes begin quickly moving, hence the name rapid eye movement. Heart rate, breathing, and blood pressure also look the same as being awake. Their muscles will be almost paralyzed other than random twitches and the person is dreaming.
A good night of sleep can be the best way to deal with stress, problems, and illness. What is a good night? It depends on the person and it changes with age. The average infant sleeps about 16 hours a day with about 50 percent of it is in the REM stage. On the other hand, the average 70 year old sleeps about 6 hours a night waking up more frequently and experiences less than 25 percent of that time in REM. Most people go through the sleep cycle between four and...