Why Do We Need Sleep?

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Why Do We Need Sleep?
Typed By: Miracle Taylor

Regulating sleep is something our bodies do that is as natural as eating, drinking, and breathing. This implies that sleeping serves a similar role in our health and well being. Even though it is difficult to answer the question “Why do we need sleep?” scientists have developed several theories that may explain why we spend a third of our lives sleeping. Comprehending these theories can help expand our appreciation of the function of sleep in our lives. Most of us recognize at some level that sleep makes us feel better. We feel more energetic, happier, more alert, and better able to function after a good night’s sleep. However the fact that sleep makes us feel better and that going without sleep can make us feel worse is just the beginning to understanding why sleep might be necessary.

One way to think of sleeping is to compare it to another one of our life-sustaining activities: eating. Hunger is a protective mechanism that has evolved to ensure that our bodies receive the nutrients that our bodies need to repair tissues, function properly, and to grow. Although it is easy to grasp the role that eating serves sleeping and eating are not as different as they may seem.

Sleeping and eating are regulated by powerful internal drives. Going without food produces the uncomfortable feeling of hunger, while going without sleep makes us feel extremely sleepy. And just as eating relieves hunger and ensures that we acquire the nutrients we need; sleeping relieves drowsiness and ensures that we obtain the sleep we need. Still, the inquiry remains: Why do we need sleep at all? Is there a single main function of sleep, or does sleep serve many functions?

All human beings need sleep- old, young, healthy, sick-need sleep. Thus, everyone should have an interest in this natural phenomenon. However, most people never question what sleep is and why they must get it. This paper will explore what goes on in our bodies when we’re in this ambiguous state called “sleep”, why it is necessary to function and how much we should be getting. What is sleep? Sleep is characterized by a number of things: a reduction in voluntary movement, decreased reaction to external stimuli, an increased rate of anabolism (synthesizing cell structures), a decreased rate of catabolism (breaking down cell structures), a stereotypic posture (lying down), and reversibility (we can wake from sleep) . Sleep can be broken down into two kinds: REM, Rapid Eye Movement, which accounts for 20-25% of sleep, and NREM, non-REM, which constitutes 75-80% of sleep. Interestingly, sleep is cyclical and occurs in 90-minute phases of REM and NREM; on a given night, a person may have between 3 and 6 NREM-REM cycles. Non-REM sleep consists of four stages of brain activity: stage 1 is the “gateway stage between wake and sleep” where theta brain waves of sleep replace alpha waves of wakefulness, in stage 2 is characterized by sleep spindles and K-complexes and awareness of the environment disappears, stage 3 is characterized by delta brain waves, and stage 4 is true deep sleep (“this is the stage where night terrors, bed wetting, and sleepwalking occur”). REM sleep is best known that period where we dream. It is interesting to note that the period where we dream is the shortest part of the whole sleep cycle, yet it is the only part we remember in the morning. Scientists have explored the question of why we sleep from many different angles. They have examined, for example, what happens when humans or other animals are deprived of sleep. In other studies, they have looked at sleep patterns in a variety of organisms to see if similarities or differences among species might reveal something about sleep's functions. Yet, despite decades of research and many discoveries about other aspects of sleep, the question of why we sleep has been difficult to answer.

One of the earliest theories of sleep,...
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