AP PSYCHOLOGY

Detailed explanation-1: -In a typical night, a person goes through four to six sleep cycles. View Source . Not all sleep cycles are the same length, but on average they last about 90 minutes each.

Detailed explanation-2: -Sleep cycles across the night are only approximately 90 minutes in length. There are lots of individual differences in cycle length and the variation may be from around 60 to 110 minutes.

Detailed explanation-3: -An average sleep cycle lasts about 90 minutes. Ideally, you need four to six cycles of sleep every 24 hours to feel fresh and rested. Each cycle contains four individual stages: three that form non-rapid eye movement (NREM) sleep and one rapid eye movement (REM) sleep.

Detailed explanation-4: -The sleep cycle is part of the circadian cycle and determines how we sleep. Each of these cycles lasts 90 minutes, although they can vary from person to person. However, it’s never less than 90 minutes or anymore than 110 minutes. Within the sleep cycle, there are five phases.