The period of NREM sleep is made up of stages 1-4. Each stage can last from 5 to 15 minutes. A completed cycle of sleep consists of a progression from stages 1-4 before REM sleep is attained, then the cycle starts over again. During the deep stages of NREM sleep, the body repairs and regenerates tissues, builds bone and muscle, and appears to strengthen the immune system. As you get older, you sleep more lightly and get less deep sleep. Aging is also associated with shorter time spans of sleep, although studies show the amount of sleep needed doesn't appear to diminish with age.
REM sleep occurs 90 minutes after sleep onset. The first period of REM typically lasts 10 minutes, with each recurring REM stage lengthening, and the final one may last up to an hour. Polysomnograms show brainwave patterns in REM to be similar to that recorded during wakefulness. In people without sleep disorders, heart rate and respiration speed up and become erratic during REM sleep. During this stage the eyes move rapidly in different directions.
Intense dreaming occurs during REM sleep as a result of heightened brain activity, but paralysis occurs simultaneously in the major voluntary muscle groups. REM is a mixture of encephalic (brain) states of excitement and muscular immobility. For this reason, it is sometimes called paradoxical sleep.
The percentage of REM sleep is highest during infancy and early childhood. During adolescence and young adulthood, the percentage of REM sleep declines. Infants can spend up to 50% of their sleep in the REM stage of sleep, whereas adults spend only about 20% in REM.
One is Non-Rapid eye movement, the other is Rapid eye movement. Other than the fact your eyes rapidly move in REM sleep and don't in NREM sleep the key difference is that it is accepted that the only time one dreams is during REM.
NREM and REM
You have the alternate episodes of REM and NREM types of sleep. REM sleep is characterized by rapid eye moment type of sleep. You can easily spot that the person is moving his eye ball and flickers the eye lids. The electroencephalogram of the patient is specific for REM and NREM sleep.
nrem
The most restorative stage of sleep is NREM-3.In a sleep cycle you progress through the stages:Initial sleep induction: NREM-1 -> NREM-2 -> NREM-3Full sleep cycle: NREM-3 -> NREM-2 -> NREM-1 -> REM -> NREM-1 -> NREM-2 -> NREM-3.A full sleep cycle takes approximately 90 minutes, but the time you spend in each stage changes during the night. At first you spend more time in stage 3, but as your body rests it will spend more and more time in REM.
True
Nrem (n1, n2, n3)
rem=remington
You do occasionally dream during NREM, but the dreams are not nearly as vivid as during REM and usually they are sparse, short and just fragments of a dream
rapid eyes movement (REM) and non rapid eyes movement (NREM)
rapid eyes movement (REM) and non rapid eyes movement (NREM)
It depends on the person, and the sleep, but the first stage averages at about 90 minutes, with stages 2-4 taking on average 100-120 minutes. The cycle generally proceeds from NREM (non-REM) stages 1-3 to REM (stage 4), back down to NREM, and back to REM, several times a night, generally ending in an REM stage before awakening.
The dreams that people have during REM are dreams that are usually illogical and bizarre. If you are awoken during REM you are more likely to remember your dream than if you were awoken during a NREM