The Sleep-Wake Cycle

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Sleep-Wake Cycle
The sleep-wake cycle is controlled by two systems, circadian and homeostatic system, that work against each other (Marhefka, 2011). The circadian system, also known as the internal clock, is responsible for regulating sleep/wake cycles as well as hormonal secretions. The homeostatic system controls how sleepy you are by increasing the need for sleep as the period of wakefulness lengthens (Alhola, Polo-Kantola, 2007). Physiologically, the circadian preferences for adolescents and young adults tend to be delayed. As adolescents become more physically mature, they usually have a lower homeostatic sleep drive, thus making them less sleepy at night (Thacher, 2008). The typical circadian period of adolescents and college students is 24.27, while older adults have a circadian period of 24.1 hours (Hershner, Chervin, 2014). Having delayed circadian …show more content…

In stage one, a sleeper experiences light sleep and can easily be awaken. When a sleeper progresses to stage two, eye movement stops and brain waves become slower (National Sleep Foundation, 2015). Stages three and four are both regarded as the deepest and most restorative sleep, with no eye movement or muscle activity occurring during this stage (Stages of sleep, 2014). During these stages, blood supply to muscle increases and tissue growth and repair occurs. On average, REM sleep occurs every 90-120 minutes, approximately 4 to five times a night if adequate amount of sleep is obtained. Each REM sleep period grows progressively longer than the previous cycle, with the last episode near rise time (Hershner, Chervin, 2014). REM sleep is essential because it provides energy to the brain and the body, thus supporting daytime performance. In order for sleepers to receive the full benefit that sleeping provides, they must go through each sleep stage for an extended period of time (Stages of sleep,

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