Four Sleep Cycles

What really goes on when we sleep? At first glance sleep is just simply sleep but so much more is going on. When we(humans) go to sleep we cycle through four different stages of sleep. Each of the four cycles are significant. When we initially fall asleep the first cycle is called the NREM1 stage. The next stage is the NREM2 stage and consist of periodic sleep spindles (Excelsior, 4TH 16, p. 1.18). The third stage is the NREM3 sleep and this simply means you are in the threshold of that deep sleep. The NREM1 and NREM2 stages each last about 20 minutes and the NREM3 last for about 30 minutes. The next stage and arguably the most studied is the REM Sleep. The REM (Rapid Eye Movement) sleep last for about an hour and is very important. This is when the brain is the most
As mentioned before the sleep spindles are active during the NREM2 stage but throughout the duration of this stage wave frequencies from the brain begin to slow down. NREM3 you are in lovely deep sleep and there is no rapid eye movement. The REM stage is when the brain is most active. These cycles do not happen just one time but rather multiple times depending on how long the person sleeps. When asleep you can get dreams in both the NREM and the REM stages and the dreams are different. According to a sleep study, researchers found that NREM dreams are not as common, they are relatively short and often derive from social interactions. Dreams that take place during the REM stage are normally motivational and emotional (Carlos Macasaet, 2005). Sigmund Freud had contributed the theory of why we have dreams and what they mean. Freud theory was that dreams were a way for people to let go of ideas and feeling that would not be socially acceptable. “The dream unites the grossest contradictions, permits impossibilities, sets aside the knowledge that influences us by day, and exposes us as ethically and morally obtuse”- Sigmund