5. REM Sleep
REM sleep is distinguishable from NREM sleep by changes in physiological states, including its characteristic rapid eye movements. Heart rate and respiration speed up and become erratic, while the face, fingers, and legs may twitch. Intense dreaming occurs during REM sleep as a result of heightened cerebral activity, but paralysis occurs simultaneously in the major voluntary muscle groups, including the submental muscles (muscles of the chin and neck). Because REM is a mixture of encephalic (brain) states of excitement and muscular immobility, it is sometimes called paradoxical sleep. It is generally thought that REM-associated muscle paralysis is meant to keep the body from acting out the dreams that occur during this intensely cerebral stage. The first period of REM typically lasts 10 minutes, with each recurring REM stage lengthening, and the final one lasting an hour.

Sleep Cycle
The five stages of sleep, including their repetition, occur cyclically. The first cycle, which ends after the completion of the first REM stage, usually lasts for 100 minutes. Each subsequent cycle lasts longer, as its respective REM stage extends. So a person may complete five cycles in a typical night’s sleep

To complete your sleep circle you need:
- Good sleep hygiene
- A consistent pattern of sleep and wake times
- Optimal spinal support and comfort
- The many healthy benefits of a sleep system designed to support nature’s renewal process