A normal, healthy individual experiences cycles of the five stages of sleep each night. Each stage of sleep has particular characteristics and each stage of sleep is important. Most individuals would agree that there is nothing more refreshing than a good night's sleep.
Falling Asleep
Stage 1 sleep is a very light sleep than an individual can be brought out of easily. The movement of the eye becomes slower in stage one sleep and the activity of the muscles slow as well. Stage 1 sleep usually only lasts for a few minutes and occurs when an individual feels like she is falling asleep.
Light Sleep with Slow Brain Waves
Like Stage 1 sleep, Stage 2 sleep lasts only a few minutes. When an individual is in Stage 2 sleep his eyes stop moving completely. Brain waves slow, though sudden burst occur in Stage 2 Sleep.
Entering Into Deep Sleep
When an individual enters into a deep sleep she is finally in Stage 3 sleep. In stage three sleep the brain experiences delta waves which are very slow brain waves. In between these delta waves an individual will experience short fast brain waves called theta waves. Normal individuals will experience anywhere between 20%-50% delta waves when they are in stage 3 sleep.
Very Deep Sleep with Very Slow Brain Waves
Stage 4 sleep is similar to Stage 3 sleep in the fact that a person in Stage 4 sleep is considered to be in a very deep sleep. When a person enters into Stage 5 sleep more than half of his brainwaves are delta waves which means his brain waves are very slow much of the time. Theta waves are still present but in lesser frequency than Stage 4 sleep. There is virtually no eye movement or muscle movement in stage four sleep.
Nightmares in Stage 4 Sleep
Stage 4 appears to be the stage in which unconscious nighttime activity occurs, particularly in children.
While in deep Stage 4 sleep children and occasionally adults will experience nightmares or sleepwalking. Children may also wet the bed when in Stage 4 sleep.
REM Sleep
The fifth stage of sleep is when rapid eye movement begins to occur. A person experiencing REM will have temporary muscle paralysis. Individual's in stage five sleep may experience an increase in heart rate and blood pressure. Body temperature will be slightly lower in Stage 5 sleep. Stage 5 is when the most vivid and memorable dreams are experienced.
The stages of sleep do not happen only once but repeat themselves throughout the night.
 |
