The
Meaning of Dreaming
The
purpose of dreaming still remais largely unexplained.
However, researchers have been proposed several theories
based on neurobiological findings and behavioral contents
of dreams.
The Content of Dreams
Many normal dreams are unpleasant. According to study
over 10.000 dreams from normal people, and found that:
64% - were associated with sadness, apprehension,
or anger;
18% - were happy and exciting;
1% - were associated with sexual involvement;
Two - Hostile acts by or against the dreamer, such
as a murder, attack, or denunciation.
Bizarre Dreams
The function of dreaming is to eliminate certain undesirable
forms of interaction between cells in the cortex that
could be prejudicial to the brain. That is, we dream
to reduce fantasy and obsession. This theory predicts
that flaws in the ability to process REM sleep, may
cause fantasies, hallucinations and obsession. They
also believe that the brain needs to get rid of information
processed during the awakened state, and that dreams
are a channel for the elimination of these informations
and for the adjustment of the brain. The responsible
agents in this search for balance, would be special
structures in the brain. In studies with neural simulation
in computer's network, an advanced technology in computational
neuroscience, which is believed to be operated in
a way similar to the brain, the authors demonstrated
that the nets became overloaded when it was attempted
to store an excessive amount of information in them.
In this case, the net produced bizarre associations
(which may be compared to "fantasies" in dreams),
and it tended to return the same result, whichever
input data were provided ("obsession"), and could
respond to inappropriate input signals, which normally
didn't produce response (hallucinations). This theory
predicts that flaws in the ability to process REM
sleep, can generate fantasies, hallucination and obsession.
Emotionals Dreams
Emotions in dreams may reflect the dreamer's personality
as well as his or her situation in waking state. Dreams
can express worries, wishes, insecurity, ideas of
grandeur, jealousy, love, fears, and other feelings
or sensations, revealing different aspects of a person's
mental state. In 70 studied individuals, the content
of dreams were strongly related to the way the person
was dealing with the crisis in question (the divorce).
This possibility could be tested by observing whether
dreams reported by subjects "artificially" awakened
during an experiment show a decrease in the proportion
of "anxiety-causing" themes.
Dreams With Anti-Social Acts and With Deceased
People
In the awakened state, the cortex analyses with precision,
impulses arriving from several receptor organs in
the sensorial system, coming to a decision and generating
an integrated response as, for example, the arm's
movement (an action of the effector organ) when picking
up a knife. The cortex manifests itself also in the
deliberate inhibition of the action (for example,
to throw the knife toward a person). The memory mixes
the past and the present; the dreamer recognizes a
dead person, but accepts its presence without surprises.
Consequently, the integration of the cortical response
is incomplete and the dreamer is many times lead to
commit imaginary anti-social acts. Happily, the impulses
of the sleeping cortex die on the way of the effector
organs and nothing bad happens. After a sudden awakening,
even normal people can become confused and act in
a disorganized way for some time. Corporal Movements
During Dreams Some of the body movements are related
to dreams' content . Edward Wolpert, from the University
of Chicago, held electrodes to limbs on sleeping s
ubjects and registered the electrical action potential
(the force applied on an electrically charged particle)
of the muscles. The register in one of the subjects
showed a sequence of motor activity first on the right
hand, then on the left hand, and finally on the legs.
Immediately awaken, the subject related that he dreamed
he had held a bucket with his right hand, transferring
it to the left hand, and then started to walk. Extending
this to somnambulism, he speculates that this disturbance
can be an extreme expression of such motor deflux
to the extremities. The Evolutive Nature of Dreams
Jonathan Winson (16) suggests that dreams reflect
an individual strategy for survival. For him, the
nature of REM dreams sustain an evolutive evidence.
During the day, animals process information in their
brains to be able to walk and move their eyes, with
the purpose of feeding, defend themselves against
predators, etc. During the night, while processing
again those informations during the REM sleep, such
re-processing wouldn't be easily separated from locomotion,
as this would demand a big revision of brain circuitry.
Then, to remain asleep, the locomotion must be suppressed,
inhibiting motor neurons (those that promotes the
locomotion). The eye movements, on the other hand,
don't need to be suppressed because its activities
don't disturb the sleep. Other theories sustain that
dreams can reflect a mechanism of memory processing
that is inherited from inferior species, in which
the important information for survival reprocessed
during REM sleep is sensorial (9). According to our
ancestral mammals, dreams in humans are sensorial,
specially visual. The congenitally blind have auditory
dreams, and those who lose their sight gradually lose
their ability to dream visually.
