Dream Interpretation - Understanding the Sleep Cycle
Before we can understand just what takes place in the dreaming
mind, and what it all means, it is a good idea to have an
understanding of the sleep cycle, and the function of dream
sleep within this sleep cycle. Dream sleep is a distinct part of
the sleep cycle, different in almost every way from other types
of sleep.
There are four distinct stages to the sleep cycle, and every
human goes through several such sleep cycles in a typical night.
The average full sleep cycle lasts from 90-120 minutes, so an
average eight hour night of sleep could contain four or more
separate sleep cycles.
Dreams may occur at any of the four stages of sleep, but the
most vivid dreams, and the ones most likely to be remembered in
the morning, occur during the REM stage of sleep. This sleep
stage is generally referred to as REM (rapid eye movement)
sleep. The name comes from the eye movements that are observed
during this stage of sleep.
Since the entire sleep cycle repeats at least four and sometimes
as many as seven, times per night, it is therefore possible and
even likely that the same person will experience several
different dreams every night. In most cases, however, the only
dreams that are remembered are those that take place closest to
waking. Not remembering dreams, however, does not mean they have
not occurred.
Let us begin our look at the four stages of sleep.
Stage 1 During the first stage of sleep, the sleeper's eyes move
back and forth in an erratic fashion. For this reason, this
stage of sleep is referred to as REM, or rapid eye movement,
sleep. This stage generally occurs from 90-100 minutes after the
initial onset of sleep. During this period of sleep, the blood
pressure rises and the heart rate and respiration speeds up and
may become erratic as well. During this stage of sleep, the
voluntary muscles become paralyzed. This stage of sleep is the
one in which the majority of dreaming occurs.
Stage 2 Stage two is a light sleep, and it is characterized by
non rapid eye movements. During this stage of sleep the muscles
are relaxed that the heart rate is slowed. This stage of sleep
prepares the body for deeper sleep.
Stage 3 and 4 Stages three and four also feature non rapid eye
movements. During stages three and four of the sleep cycle, the
body enters into a deep sleep. You are completely asleep during
both stages, but stage four is more intense than stage three.
All four stages of sleep repeat themselves throughout the sleep
period, generally occurring from four to seven times. Each time
the sleeper enters REM sleep, dreaming occurs. Sometimes
dreamers remember dreams from earlier in the night, but in most
cases the dreams that are remembered are those that occur
closest to waking.
Researchers know, however, that dreaming occurs during all four
to seven sessions of REM sleep. They know this through their
work with volunteers who agree to be awakened during REM sleep.
Those awakened during REM sleep generally provide very vivid
descriptions of those dreams, as do those who awaken naturally
during a particularly vivid, intense or frightening dream.