Sleep consists of a cyclical pattern that shifts between non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. Through the night, or whenever you sleep, your brain goes through different cycles with each lasting about 90 to 120 minutes.
Each cycle has a different depth that ranges from light sleep stages (N1 sleep) to deeper, slow-wave sleep (N2 and N3 sleep). The deepest cycle is REM which occurs during the latter part of your sleep as it alternates with the N2 sleep cycle. The REM cycle, therefore, is not only the cycle during which dreams occur but can also lead to various sleep issues if constantly interrupted. That’s when sleep architecture comes into play.
Sleep Architecture is basically a method that allows us to picture this complex pattern that occurs over the course of the night through the use of a hypnogram. It describes each of the different cycles of sleep as well as help us understand the consequences of sleep interruptions during each one. Like other aspects of our bodies, it is impacted by both age and sleep disorders. As we become older, our sleep architecture changes through an increase in N1 cycles and a decrease in slow-wave sleep cycles. This change causes interruptions of sleep during the night which, in turn, might lead to insomnia.
Other sleep disorders also change the shape of your sleep architecture. This can occur if the REM cycle happens early in the sleep process and might have several causes. One cause is Narcolepsy which is a sleep disorder that causes deep REM sleep to occur at a much quicker rate than usual. Other causes can be irregular sleep-wake rhythm caused by disorders such as sleep apnea, withdrawal from anti-depressants and depression.
Written by: Milisia Fam
- Brandon Peters, MD, a board-certified physician. “Sleep Architecture Represents the Cyclical Pattern of Sleep.” Verywell, http://www.verywell.com/what-is-sleep-architecture-3014823.