What Is Sleep?
Author: Gary M. Miller

Sleep is one of the essential routines in our daily lives. We
start to feel a bit drowsy as the clock reaches a certain time
and we know it is time to lie down and close our eyes for a
while. We have to sleep so that our bodies can refuel for the
next day. Sleep is something that is simply programmed into our
bodies. We know this because it is commonly seen that people
eventually sleep even if they don't want to! This is because
their bodies simply demand it.

Sleep goes on for roughly one-third of our total life which
shows how important it really is. It is an important activity
that, if not spent wisely, will eventually detract from your
work and cause severe problems in your life. People just aren't
as good at anything as they are when they have had enough sleep.
We know that we should not neglect our sleep because it is
crucial for our motor and our cognitive functions. In order for
us to survive in this world, we simply need to sleep.

In a test on rats, those who were deprived of sleep died within
two to three weeks. Scientists have learned that it is crucial
for both animals and people to sleep in order to be alert and
functioning each day. In scientific terms, we now know that the
activity of the brain regulates the amount of sleep that is
needed by the body. Researchers use electrodes and
electroencephalograms (EEG's) to measure electrical activity in
the brain, eye movement, and muscle tension. These are all
examined to determine many facts about sleep in general. The
results show certain patterns which then lead to finding out
about the various stages of sleep.

There are two basic stages of sleep which are rapid eye
movement (REM) and non-rapid eye movement (NREM). NREM sleep is
composed of four stages in terms of the amplitude and frequency
of the activity of the brain waves. The pattern of NREM sleep on
the brain waves is slower, more regular, and of a higher voltage
than that of wakefulness. When you are in a deep sleep, the
brain waves move slower and have bigger amplitude. The first
stage of NREM sleep is very light sleep. Stage two NREM,
however, has two kinds of brain waves that are present. They are
called sleep spindles and K complexes. Stage three and four of
NREM has incrementally higher voltages and slower waves. By
stage four NREM, it is extremely hard to wake a person up. This
could also be referred to as "sleeping like a log".

REM sleep is the second basic stage of sleep. It is described
by eye movements that bounce around underneath a person's
eyelids in an extremely rapid fashion. The eye movements do not
necessarily move all the time but they may suddenly zoom up and
down or back and forth, stop for a while and then dart back and
forth again intermittently. During REM sleep, the activity shows
very fast and irregular activity. It is a lot more spontaneous
than in the NREM sleep. The person's muscle tone also goes limp
although the major muscles like the heart, diaphragm, eye
muscles and

blood vessels are still active. The state of the body in this
stage is almost like being paralyzed. This is because the
electrical activities in the muscles are almost completely
stopped. There may be some small twitching in these muscles but
mostly there is nothing during this stage.

Sleep is a cyclical process where NREM and REM sleep will
repeat in cycles. It starts with an NREM phase which last for
roughly ninety to one hundred and ten minutes. Then it recurs
four to six times per night. As the night progresses, the extent
of NREM sleep decreases and the extent of REM sleep increases.
Also, blood flow to the brain, airway resistance, sexual
arousal, respiration and blood pressure increase. Sleep is a
broad topic and it is intimately connected to a person's age in
how it functions. Biological clocks, homeostasis, dreams, and
sleep practices all play a part in how living things sleep. The
science of sleep is so complex that we should all take care to
get the correct amount of sleep. It is one of the most important
things you will ever do!


About The Author: Over 70 Million people in the USA suffer from
some kind of Sleep Disorder! There are actually hundreds of ways
to improve your sleep but the first thing that is needed is to
raise more awareness! If you want to sleep better tonight , you
can visit this information Sleep Aid Web Site that is packed
with FREE information: http://www.Sleep-Aid-Solutions.com