Translations:Scheduling overview/6/en

NREM Stage 3, accounting for 15-25% of total sleep, is the deepest of all sleep stages. This stage contains primarily delta waves, which are high-amplitude and low-frequency. Hence, this stage is also known as slow-wave sleep (SWS). It is very difficult to wake up from this stage; attempts at doing so tend to result in sleep inertia -- a period of intense grogginess and impaired cognitive function. This stage of sleep plays a critical role in the maintenance of the brain through the glymphatic system. This process takes about 30 to 60 minutes of continuous NREM3 to complete, and could be hindered by schedules containing only short naps.