4 cycle progression of electrical activity that is recorded by an EEC. Stage 1 is marked by drowsiness; stage 2 is light sleeping, stage 3 and 4 show delta waves and consists of deep sleep. These stages are interrupted by REM sleep.
4 cycle progression of electrical activity that is recorded by an EEC. Stage 1 is marked by drowsiness; stage 2 is light sleeping, stage 3 and 4 show delta waves and consists of deep sleep. These stages are interrupted by REM sleep.