Scientific experiments suggest that an average human goes through several stages of different depths of sleep. The experts, after studying EEG experiments conducted on various subjects, have divided sleep into four stages. An EEG gives a “wave” like record of the activity of the brain. Let us call the activity of brain, in terms of EEG records, “a brain wave”. These waves are nothing but very small voltage changes. The number of voltage changes per second, i.e., the frequency of the electrical changes, and the scale on which these changes occur tell us how deep a sleep a person is in. That frequency varies from 1 to 50 Hz; 1 or 2 in deep sleep and 50 or more in highly active state. In stage 1 of the sleep, a relatively large proportion of the brain activity is fairly fast; in stages 2 and 3, the proportion of slower activity increases; and in stage 4 a large proportion of very slow (1-3 Hz) activity is shown.
The sleep pattern through the night is cyclic in nature, meaning that a person goes from lower stage sleep to higher stage sleep and back again, generally, 4 to 5 times. But when her brain returns from deep sleep stages, it does not go to the stage 1 sleep, instead it goes to a stage called “paradoxical sleep“. During paradoxical sleep, the brain shows the activity that looks very much like of awaken state, yet people in paradoxical sleep are deeply asleep; which can be concluded by the intensity of stimulation needed to wake them.
It is the state of paradoxical sleep when most (80-90%) dreams occur. During paradoxical sleep the muscles of the body go limp — a defense mechanism of the brain, otherwise the dreams may cause so much stimulation that if the body is not limp, a person can end up hurting the self or someone else. The eyes move rapidly from side to side, so paradoxical sleep is also called Rapid-Eye-Movement (REM) sleep.
So, what are dreams?
Freud’s interpretation of dreams was based on repression. He considered dreams to be expressions of forbidden sexual or aggressive urges. If our constant urges and wishes were expressed directly, they would be very disturbing and can prove strong guilt or anxiety if we become aware of them in ourselves. So their expression in dreams is hidden behind a disguise — the actual content of the dreams.
Dream interpretation is a difficult art, at best, or a science for which our axioms have no or little basis. It is complicated by several problems. One is that the symbols we use in our dreams have highly personal meanings, though the analysts believe that we use certain common symbols to stand for particular ideas. The other complication is due to the fact that parts of the dream may seem illogical or confusing. Another is that parts of the dreams are forgotten — mostly the ones that are most disturbing. The subject reporting her dream may try to correct for these faults and the result can be a distortion of the dreams as actually experienced. As an example, let us take Freud’s self-analysis through one of his boyhood dreams:
In Freud’s dream, his sleeping mother was taken into a room and laid on a bed by strange people with bird beaks. The beaked creatures reminded Freud of some illustrations he had seen in an edition of Bible called Philippson‘s. With still more analysis, Freud associated the name Philippson with Philipp — an “ill-mannered boy” who had taught Freud a vulgar German word for sexual intercourse. This word, völgen, is derived from Vogle, which means “bird”. Thus Freud made sense of the birdlike humans in his dreams; they, and their behavior, represented his own sexual feelings towards his mother.