We feel the urge to sleep when waves of tiredness fall upon us that has been accumulated along the day. After a good rest, we can feel the burden of physical and mental fatigue removed from our body.
Through this, we can emit a question, “Do people sleep to relieve stress?”.
Although this is the significant answer to the question, there are other reasons why sleeping is crucial to our body.
1 Necessary Energy source; Sleep
One way to think about the function of sleep is to compare it to another of our life-sustaining activities: eating. Hunger is a protective mechanism that has evolved to ensure that we consume the nutrients our bodies require to grow, repair tissues, and function properly.
2 Sleep is crucial for LEARNING
Studying mice, scientists at Johns Hopkins have fortified evidence that a key purpose of sleep is to recalibrate the brain cells responsible for learning and memory so the animals can “solidify” lessons learned and use them when they awaken. Without at least 4~6 hours of sleep, more than 40% of the content one studied are not solid in the recollective systems in one’s brain. For young infants 11~13 hours of sleep is required for this ability to function correctly.
But still, the answer to the question cannot be satisfied with the pre-suggestions, for the question is asking for the fundamental reason why animals started the action, “sleeping”.There are several theories to clarify the reason to this action that existed to all living organisms from birth .