DREAM

a hallucinatory experience that occurs during sleep. Although the visual aspect of dreams is usually most vivid, in some cases dreams are primarily auditory. Dream reports range from the very ordinary and the realistic to the fantastic and the surreal. Mankind has always attached great importance to dreams; however, conceptions of their source and significance have changed tremendously over the centuries. In the ancient world, the belief was prevalent that dreams were sent by the gods, and they were considered as a means to predict the future and devise cures for the ill. Nearly four thousand years ago, the Egyptians catalogued interpretations of dreams, and prophetic dreams are mentioned in many Middle Eastern and Asian texts, including the Bible. While the ancient Greeks generally shared the belief in the predictive power of dreams, it is notable that Aristotle discussed dreams in a more scientific manner, stressing the roles of sense impressions and the emotions. However, it was not until the 19th century that widespread belief in the divine source of dreams began to ebb. At that time, Alfred Maury made an exhaustive study of dreams and concluded that they resulted from the misinterpretation of sense impressions during sleep (e.g., a loud sound during the night stimulating a dream of a thunderstorm). Modern theories of dreams have stressed that they are extensions of the waking state. In the late 20th century, the study of dreams has focused on two topics: the physiological process of dreaming and the content of dreams. Researchers have found physiological clues as to when a dream is actually taking place. The principal dream period, marked by a combination of rapid eye movement (REM), a brain-wave pattern similar to that produced during wakefulness, and increased physiological activity, is called REM sleep (or the D- state). Since its discovery in the mid-1950s, researchers have conducted experiments in which they awaken subjects who show signs of REM sleepin most cases the subjects report intensely the experience of vivid visual dreams. Subjects awakened while not in REM sleep report dreams less frequently and have more difficulty remembering them. Thus, the evidence supports a close association between REM sleep and the experience of vivid, spontaneously recalled dreams. Extreme behavioral manifestations such as night terrors, nightmares, enuresis (bed-wetting), and sleepwalking have been found to be generally unrelated to ordinary dreaming. REM sleep recurs about every 90 minutes throughout the time spent asleep, in periods that successively grow in duration from an initial length of 10 minutes. Between the ages of 10 and the mid-60s people spend about a quarter of their time asleep in REM sleep. If this amount is temporarily lowered owing to the ingestion of certain drugs or by waking a sleeper in REM sleep, as soon as permitted the person will recover by increasing his or her REM sleep percentage, accompanied by an increase in dreaming. Although the presence of REM sleep indicates a high probability that a person is dreaming, the content of his or her dream is directly available only to the dreamer. Thus, to study the contents of dreams, researchers must rely on reports made by dreamers after they awaken. Unpleasant feelings in dreams are reported almost twice as often as pleasant ones. The contents of most dreams seem to consist of fairly direct representations of people and settings familiar to the dreamer. The sense of strangeness that accompanies dreams is thought to result from the sharp discontinuities in time and place occurring in dream events. Dreams have provided creative solutions to intellectual and emotional problems and have offered ideas for artistic pursuits. A famous example is drawn from science: the German chemist August Kekule, while struggling to find the structure of the benzene molecule, dreamed of a snake biting its tail and, on waking, realized that benzene has the form of a ring. It seems that a type of cognitive synthesis occurs subconsciously during dreaming, which facilitates conscious insight. Perhaps the most famous theory of the significance of dreams is the psychoanalytic model developed by Sigmund Freud in The Interpretation of Dreams (German: Die Traumdeutung; 1900). In Freud's view, the events of a dream (the manifest content) are produced by the so-called dreamwork, whose task is to give disguised expression to unconscious desires (the latent content). These desires are ordinarily kept out of consciousness (repressed), because they represent forbidden impulses, often of a sexual nature. During sleep, the force of repression is reduced, hence repressed desires can be safely expressed. But to prevent these unacceptable desires from emerging in an explicit form into the dreamer's consciousness, the dreamwork transforms them into acceptably disguised or symbolic images by drawing on sensory stimuli, waking experiences, and deep-seated memories. A central therapeutic technique employed in psychoanalysis is the interpretation of a patient's dreams, in the effort to understand the workings of his or her unconscious mind. a hallucinatory experience that occurs during sleep. Dreaming, a common and distinctive phenomenon of sleep, has since the dawn of human history given rise to myriad beliefs, fears, and conjectures, both imaginative and experimental, regarding its mysterious nature. While any effort toward classification must be subject to inadequacies, beliefs about dreams fall into various classifications depending upon whether dreams are held to be reflections of reality, sources of divination, curative experiences, or evidence of unconscious activity. Additional reading Two differing classic theories of dream interpretation are found in Sigmund Freud, The Interpretation of Dreams, vol. 4 and 5 in The Standard Edition of the Complete Psychological Works of Sigmund Freud, edited by James Strachey (1953, reprinted 1981; originally published in German, 8th ed., 1930), also available in other translations; and C.G. Jung, Dream Analysis: Notes of the Seminar Given in 19281930 (1984). Also see G.E. Von Grunebaum and Roger Caillois (eds.), The Dream and Human Societies (1966), a scholarly work, with a chapter on dream research; Richard M. Jones, The New Psychology of Dreaming (1970, reissued 1978), which attempts to coordinate experimental findings on dreams with classic theories; Rosalind Dymond Cartwright, Night Life: Explorations in Dreaming (1977), which covers a series of studies approaching a laboratory-based understanding of dreams and dreaming; Montague Ullman and Nan Zimmerman, Working with Dreams (1979, reissued 1985), which helps the general reader understand and work with dream material; and Ernest Hartmann, The Nightmare: The Psychology and Biology of Terrifying Dreams (1984), a comprehensive work. Wilse B. Webb Rosalind D. Cartwright