Four Stages Of Sleep

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Have you ever heard the saying “I am shutting down for the night?” It is a common misconception throughout the world that the body shuts down during sleep. However, sleep is the period of time in which the brain becomes extremely active. There are four stages of sleep that our bodies go through each night. During each of these stages specific parts of the brain complete tasks that will help to improve our daily lives. There are several parts of the brain that are active while we sleep and each part performs a specific job. During the time of which we spend sleeping, there are eight main parts of the brain that start their day of work. The hypothalamus is a “peanut-sized structure deep inside the brain.” The hypothalamus consists of nerve cells,…show more content…
These stages are stage one non-REM sleep, stage two non-REM sleep, stage three non-REM sleep, and REM sleep. “Each is linked to specific brain waves and neuronal activity.” When we first start to doze off we enter stage one non-REM sleep. This stage lasts five to ten minutes and sleep during this stage is relatively light. During this time our heartbeat, breathing, and eye movements decrease. Our muscles begin to relax and occasionally twitch as well. The brainwaves at this time also begin to slow from their normal daytime patterns. The waves become very uniform and are typically categorized as alpha and theta waves. When we enter stage two non-REM sleep our breathing and heartbeat slow even more, along with the muscles relaxing even more than in stage one. At this time our body temperature decreases and eye movements come to a complete stop. The activity of brain waves during this time decreases, but is interrupted at times by small bursts of electrical activity that are very rapid. Sleep specialist refer to these small bursts as sleep spindles. Stage two of non-REM sleep is the stage that is repeated the most throughout the night and it lasts for about ten minutes each time. Stage three non-REM sleep is the stage in which deep sleep occurs. This stage lasts for approximately thirty minutes, but takes a longer time to complete during the first half of the time we spend sleeping. During this stage our…show more content…
One of the most common brain activities during sleep is dreaming. Scientist still to this day do not fully understand why we dream or what dreams are exactly. “Some experts suggest that dreams represent the replay of the day’s events as a critical mechanism in the formation of memories, while others claim that the content in dreams is simply the result of random activity in the brain.” It is known that visually intense dreaming occurs most commonly in the REM sleep stage. Dreaming causes the brain to become very active, and not only at displaying the images we see during our dreams. A major part of the brain activity that takes place during dreaming is temporarily paralyzing our muscles. When we enter REM sleep our brain sends a message to the spinal cord telling it to “turn off” our motor neurons. This happens so that we do not act out our dreams. Another job that the brain completes during the night is disposing of unimportant information. On the opposite side, the brain also remembers important information that we have learned. “Experts call this consolidation, and it’s important for protecting against further information loss as well as boosting your ability to learn while you’re awake.” Storing important memories is another task that the brain takes on. Our brain chooses memories that it thinks are most important to us and intensifies those experiences in our mind. While the brain is

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