Identify the different stages of sleep and describe the cyclical pattern of sleep through the night. Give an example of something that can change your sleep architecture and describe how it will change the normal sleep pattern.

Question

What will be an ideal response?

Answer 1

There are five stages of sleep, which we cycle through in about 90 minutes. The first stages are identified as non-REM sleep. Stage 1 is light sleep, which starts off with alpha waves that eventually become theta waves. It is still easy to wake someone in Stage 1 sleep. A person moves into Stage 2 sleep after about 10 to 15 minutes in Stage 1 sleep. In Stage 2 sleep, the person can still be woken. Sleep spindles start to appear in this stage, which are thought to play a role in keeping a person asleep. This stage is preparing the person for the later, deep sleep stages. As the person moves into Stage 3 sleep, slower delta brain waves appear. When the majority of the brain waves are delta waves, the individual is considered to be in Stage 4 sleep. Stages 3 and 4 are deep levels of sleep, and it is difficult to wake a person in these stages. People are usually in deep sleep stages for about an hour, at which point the person will cycle back through lighter sleep stages, and then move into REM sleep for about 15 minutes. When a person moves into REM (rapid eye movement) sleep, the brain wave patterns are very active and are similar to when a person is awake. If you wake someone up during REM sleep, they will usually report that they were dreaming. The sleep cycle involves people moving from Stage 1 through Stage 4 sleep, then back to lighter sleep, and then to REM sleep. People will cycle through these stages throughout the night. Sleep architecture describes the specific pattern or structure of how much time a person spends in the various sleep stages. Student answers may vary about what can affect their sleep architecture, but the example and description should include how the disruption results in less restful or less restorative sleep.