Sleep

Ultradian Rhythms- Ultradian rhythms have more than one complete cycle every day. An example of this is sleep which consists of a 5 stage cycle which is repeated roughly every 90 minutes, multiple times throughout a single period of sleep...

The stages of Sleep-Stage 1... Stage 1 is the beginning of the sleep cycle, and is a relatively light stage of sleep. Stage 1 can be considered a transition period between wakefulness and sleep. In Stage 1, the brain produces high amplitude theta waves, which are very slow brain waves... This period of sleep lasts only a brief time (around 5-10 minutes), and if you awaken someone in the stage, they might report that they weren't really asleep...

 Stage 2-the second stage of sleep and lasts for approximately 20 minutes... The brain begins to…