Stages Of Sleep

Most people think that sleep consists of one long and dreadful snore. You just fall down on the bed and sleep and wake up either groggy-eyed or refreshed. For others, sleep is just a sweet succor and wouldn’t care to break their head over the technicalities of sleeping. But pause a second before closing your eyes, and if you care to think a little deep you will marvel at the fact that the world of sleep is as interesting as awakening. When you go to sleep, the body and mind simply doesn’t shut the shop until you wake up. In fact, at various phases of the sleep the body and the brain undergo various forms of transitions that help in giving you a proper repose. These phases of sleep have been classified into five stages, which describe the entire sleep structure of a person. All of these stages explain how our body and mind behave during sleep. Detailed below in the article are the various stages of sleep.

Sleep Cycle Stages

Stage One

This is the stage where the person just falls asleep. This stage falls under the non-REM category of sleep. Stage one is that period, where the sleeper just “drifts off”. In most sleepers, this stage lasts for about ten minutes. The sleep is very light and the sleeper can be easily awakened. Dreams and drifting thoughts also occur at this stage. The main characteristic of this sleep are:

Slow and even breathing
Regular heartbeat
Fall in the blood pressure
A decrease in brain temperature
Reduction in the blood flowing to the brain
No body movement and if there is then it is very little

Stage Two

This is also a non-REM sleep and is an intermediate stage. This stage lasts for about twenty minutes. Here, the sleeper gets deeper and deeper into sleep and so is difficult to awaken. The main characteristic of this stage are:

The brain waves are larger.
Occasionally, there is quick bursts of activity.
The sleeper will be so detached from the outside world the he/she won’t see anything even if the eyes are opened..
Sounds can easily awaken the sleeper.
There is a decrease in blood pressure, metabolism, secretions and cardiac activity.

Stage Three

In this non-REM stage, the sleep begins to get deep. This stage comes after 45 minutes of first falling asleep. The main characteristics of this stage are:

The brain waves increase to five times the size of the waves at stage two and hence, they are very slow which is at the rate of 0.5 to 4 per second.
The sleeper doesn’t awaken easily.

Stage Four

The sleeper sleeps the deepest at this non-REM stage. This stage is characterized by:

The brain waves become very large.
The sleeper is transported into virtual oblivion.
Those who sleepwalk or bed-wet are likely to do those activities at this stage.
All body functions subside to deep physical rest.
After waking up from this stage of sleep, the sleeper will be confused, disoriented and groggy. They will experience ‘sleep inertia’ and can’t seem to function properly for some time. After this stage the sleeper returns to stage two and then enters stage five.

Stage Five

This stage is known as the REM sleep stage. In this stage, the brain becomes more active. Most dreams occur at this stage. The main characteristics in this stage are:

There are big bursts of eye activity.
The brain waves are small and irregular and resembles a waking person more than a sleeping one.
While the previous four stages are characterized by relaxation, in this stage, there is enhanced body activity.
The blood pressure and the pulse increase.
There is a decrease in oxygen consumption and so the breathing gets irregular.
There is a twitching of the face, toes and fingers.

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