Within the last 100 years, sleep scientists have begun to chart the various stages of sleep. In particular, two main sleep stages have been discovered, namely REM sleep and non-REM sleep. Furthermore, within the non-REM stage, 3 stages have been proposed to...
There are 4 stages of sleep that people undergo throughout each sleep cycle, which typically lasts about 90 minutes. There is light sleep, which is characterized by low frequency brain waves. This state acts as a transitional phase into the deeper sleep states. Deep...
