(6 of 6)
The waves on the EEG showed when the sleeper's eyes were moving. Slow eye movements, taking three to four seconds, occurred when the sleeper was moving the position of his body. But rapid, almost flickering eye movements, now abbreviated in the trade jargon to REMs, occurred in varying stretches of five minutes to an hour, several times during a night's sleep. By waking and questioning their subjects after a REM period, the researchers found that they nearly always recalled having just finished a dream. By checking their EEG tracings with what their subjects told them, the Chicago researchers learned that:
>Most people dream four to five times a night.
>Dreams may last a few minutes to an hour, but average 20 minutes. >Events in a dream happen about as fast as corresponding events in reality. > Occasionally a sleeper has a series of related dreams, like soap-opera installments, and sometimes a common thread runs through two or more dreams like a leitmotiv. >Outside events, such as the noise of opening and closing doors, are rarely incorporated in the dreamer's libretto.
Guardian of What? Though such facts have been established, the basic question remains: Why does anybody dream at all? Kant and Schopenhauer equated dreams with insanity. Freud called dreaming "the guardian of sleep"; he concluded that the sleeper dreams of problems (often heavily disguised) that boil up in his unconscious because they are too painful or threatening for the conscious mind to face. The dream, he said, preserves sleep by offering a palliative for the problem.
Dr. Dement devised an ingenious experiment to find out what happens if a person is allowed to sleep his normal number of hours, but is not allowed to dream. His volunteers were awakened whenever their REMs indicated the beginning of a dream. Then they were allowed to fall asleep again. And so on, night after night. By the third night, most volunteers began to get edgy and act strange. In the final part of the experiment, when they were allowed to sleep as long as they wanted, they dreamed twice as much as usual.
Dr. Dement concluded that dreaming may be even more than the guardian of sleep: it may be the guardian of sanity itself, as sleep is the guardian of general health.