The Mind: Learning Through Dreaming

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As Freud saw it, dreams provide psychic gratification for suppressed desires. Researchers in the growing science of sleep-watching suspect that their mysterious function is much broader than that. The latest findings, as presented to the annual meeting of the Association for the Psychophysiological Study of Sleep, are beginning to confirm the link, hitherto experimentally unproved, between dreams and conscious functioning. In dreaming, the experts now surmise, the healthy mind brings its emotional experience to bear on the stresses of the day and forges new mental mechanisms for dealing with them when they recur.

The source of this conviction was the discovery of a distinct phase of normal sleep which is known as REM. At fairly regular intervals during the night, the electrical waves of a sleeper's brain become as active as they are during wakefulness, and his eyeballs dart and swivel in a series of rapid eye movements (REMs). During these periods of REM sleep, which typically last 20 to 30 minutes, the sleeper is most likely to dream.

Instinctive Chickens. One hint that REM sleep may help creatures master and retain new experiences came from research on chickens. Instinct-driven chicks do most of the learning essential to their existence during the first 24 hours of life. It is then that they become attached to one very special cozy object; normally this is a mother hen, but under laboratory conditions they will accept such surrogates as an old shoe or a ball and learn how to recognize them. According to Dr. Ramon

Greenberg of the Veterans Administration Hospital in Boston, chicks during this particularly crucial period spend almost all their sleep in REM. Then, for the rest of their lives, they do without it almost completely.

No one really knows for sure whether animals in REM sleep actually dream, but they apparently undergo a learning process. University of California Psychologist William Fishbein has found that laboratory mice taught to expect electric shocks at the end of laboratory alleyways develop amnesia about their painful experience after they have been deprived of REM sleep. It is now provable that the more advanced a creature is, the more it can learn—and the more REM sleep it has. Humans in infancy, learning more intensely than they ever will again because everything is new to them, spend 50% of their sleep in REM, compared with 20% for adults.