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D-State another stage
that modern sleep researchers have studied. D-State meaning desynchronized or dreaming, is
something all mammals do. These would include monkeys, dogs, cats, rats, elephants,
shrews, and opossums. There have also been reported that some birds and reptiles have
D-State dreams. Using a surgical procedure researchers examined selected parts of animal
brain structure. It clearly illustrated that the D-State relies on a certain area within
the brain stem known as the " pontine tegentum." According to evidence
researchers found that D-State sleep is related to a mechanism involving a bodily fluid
called "norepinephrine" while ther stages of sleep involve another type of
chemical. The changes found in D-State sleep
are increased heart and breath rate and relaxed skeletal muscles (in lower animals) and in
humans. There is also the reduction of electrical activity in muscles. This is usually
expressed in areas of the base of the tongue, in penile erections, and increasing vaginal
blood flow and uterine contractions.
Approximately in our last 6 ½ to 7 ½ hours of our sleep
during D-State, we are likely to waken by ourselves about 40 percent of the time. There is
evidence that the amount and kind of dreams we have depends on how rapidly we are roused
and on the intensity of the effort to recall. There are some people that recall their
dreams more than the average, and there are those who also rarely recall them at all. |
