3 TO 5 CYCLES PER NIGHT CONSISTING OF 5 STAGES (I - V AND REM)
FREQUENCY OF ELECTRICAL ACTIVITY DECREASES AS AMPLITUDE INCREASES
BY STAGE 4 HEART RATE AND BLOOD PRESSURE HAVE DECREASED WHILE GI MOTILITY INCREASES (PARASYMPATHETIC ACTIVITY)
REM SLEEP TAKES THE BRAIN FROM STAGE 4 BACK TO STAGE 1 (SYMPATHETIC ACTIVITY)
REM SLEEP IS ASSOCIATED WITH VISUAL DREAMING