Everyone needs to sleep, everyone loves sleep, but do you know what sleep is? Explore this article for an insight into what sleep really is and its stages.
Sleep is a state of physical and mental rest. During sleep a person becomes comparatively inactive and almost absolutely unaware of the surrounding environment. For a layman to understand sleep better, it is best described as a partial detachment from the world. It is when all external stimuli cease to affect the senses. Most people tend to take sleep for granted, but did you know that it is almost impossible for a human being to live without sleep. In fact the record for the longest period without sleep extends to eighteen days, twenty-one hours and forty minutes! During this agonizing period, the record holder reported paranoia, slurred speech, memory lapses, concentration lapses, blurred vision and hallucinations. It is complications like these that have permitted sleep to enjoy as much importance as it does. Go ahead and read on to gain an insight into the stages of sleep. Once done with gaining familiarity with the stages, you probably wouldn’t live to see another day where you don’t thank the good Lord above for the gift of sleep that you enjoy!
Stages Of Sleep
The first stage of sleep begins when a person first feels drowsy. During this stage, a person’s eyes begin to close; his/her breathing gets more regular and evenly spaced out and rolling eye movements get a lot slower. The person is not completely aware of his/her surroundings, but still can be easily aroused back to wakefulness. In this stage it’s not like the person is in a deep slumber and cannot be woken up. The stage is most likely to occur when a person first begins to feel sleepy, maybe when he/she is watching television or playing party to an excessively boring lecture. The first stage of sleep almost always lasts for ten minutes and accounts for a little less than five minutes of total sleep time in adults.
The second stage in the sleeping cycle begins when a person becomes less aware of his/her surroundings. However, the person can still be woken up easily. Here too, it’s not like they’re in a deep slumber. This stage is characterized by a slow heart rate, a decrease in body temperature and relaxed breathing. The brain begins to show signs of activity that are known as sleep spindles and K-complexes. Such activity is not seen during drowsiness or even when the person’s awake.
Stage 3 and 4
The third stage and fourth stage begin when a person’s brain activity reaches new lows. These stages are also known as the stages of ‘slow wave sleep’. In these stages, unlike the first and second, it is difficult to get the sleeping person back to a stage of alertness. The third and fourth stages of sleep are most likely to occur within the first hour of a person hitting the sack. These stages are those stages of sleep that occur between drowsiness and rapid eye movement sleep or ‘REM sleep’.
REM or rapid eye movement sleep occurs when the activity in the brain reaches chaotic levels. You may not be aware of this, but during REM sleep the brain is almost as active as it is when a person is fully awake. This holds true in spite of the person lacking awareness on his/her surroundings during the stages of REM. Dreams too are most likely to occur during REM sleep. Although dreams can envelop a person during other stages of sleep, bizarre and story-centered dreams are most likely to occur during REM sleep. During REM sleep, a person’s body is in a state of stillness, however, slight movements and twitching can be safely considered a norm.
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