Calculating sleep cycles entails figuring out the length and timing of the distinct levels of sleep an individual experiences all through the night time. These levels, usually repeating in cycles of roughly 90 minutes, embody gentle sleep, deep sleep, and speedy eye motion (REM) sleep. Understanding these patterns may be achieved by varied strategies, together with sleep diaries, actigraphy (wrist-worn motion sensors), and polysomnography (sleep research carried out in a laboratory setting). For example, an actigraph would possibly reveal that an individual spends a median of 20 minutes in REM sleep throughout every cycle.
Optimizing sleep timing based mostly on these cyclical patterns can result in extra restful and restorative sleep. Waking up throughout lighter sleep levels could make one really feel extra refreshed, whereas interrupting deep sleep may end up in grogginess. This data has sensible functions in scheduling alarms, planning naps, and addressing sleep disturbances. Traditionally, understanding sleep cycles developed alongside broader developments in sleep science all through the twentieth century, evolving from preliminary electroencephalography (EEG) observations to extra subtle monitoring applied sciences and analytical approaches.
