a continuous cycle from deep sleep to Almost-Awake moments and back to deep sleep again
A sequence of sleep stages that usually begins with a period of about 80 minutes of NREM sleep followed by about 10 minutes of REM sleep. This cycle of approximately 90 minutes is repeated four to six times each night. If the sequence is interrupted (for example, by external noise or a sleep disorder), the quality of sleep can suffer.
the cycle in which non-REM and REM sleep alternate in 90- to 110- minute phases. A normal sleep pattern has 4 to 5 sleep cycles.
term used by scientists and sleep researchers to describe the pattern of sleep stages, especially the NREM-REM cycle
A period that includes all the stages of sleep before repeating. These generally last around 45-90 minutes each.
Synonymous with the NREM-REM Sleep Cycle.
The progression through an orderly succession of sleep states and stages. In a healthy adult, the first cycle is always initiated by going from wakefulness to non-REM sleep. The first REM period follows the first period of non-REM sleep to complete the first sleep cycle. The two sleep states continue to alternate throughout the night with an average cycle period of about 90 minutes. A full night of normal human sleep will usually consist of 4-6 non-REM/REM sleep cycles.
NREM-REM Sleep Cycle is a period during sleep composed of a NREM sleep episode followed by a REM sleep episode. Each sleep cycle is equal to each NREM-REM sleep couplet with the average duration in adults being 90 minutes. An adult sleep period of 6.5-8.5 hours generally consists of four to six cycles.
Synonymous with the non-REM-REM sleep cycle