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Allan Hobson has recently proposed a new theory of REM sleep dreaming as a protoconscious state upon which consciousness is constructed. Rather than viewing dreaming as an unconscious state in conflict with consciousness, Hobson theorizes that neurones, whose address and chemical identity are determined genetically, interact and self-organize so as to generate first REM sleep, then NREM sleep and finally waking. The mammalian brain is thus automatically equipped before birth with an integrated model of the self, self-as-agent, movement, perceptual space, and emotion. In later waking periods, external information is organized and incorporated into what will become dreaming and waking consciousness. Hobson turned to neurophysiology in 1961 because of his disappointment with psychiatric psychology. Educated at Wesleyan (AB 1955) and Harvard Medical School (MD 1959), he was shocked at the ignorance and arrogance of the psychoanalytic psychiatrists at the Massachusetts Mental Health Center, Harvard's flagship teaching hospital where he began his residency. At the NIMH in Bethesda, he was introduced to sleep and dream research by Frederick Snyder and Edward Evarts. He learned more about experimental approaches to the animal model of REM from Michel Jouvet in Lyon, France. In the laboratory of Elwood Henneman, Hobson learned to record from single neurones in unanesthetized animals. In 1968, Hobson founded the Laboratory of Neurophysiology at Massachusetts Mental Health Center. Working with Robert McCarley, he developed the reciprocal interaction model of sleep cycle control (Science, 1975) and the activation-synthesis model of conscious state determination (American Journal of Psychiatry, 1977). These theories formed the basis of a brain-oriented theory of dreaming radically different from that of Freud. Tests of the physiological model followed throughout the 1980's. Strong evidence for the cholinergic genesis of REM sleep was collected with many collaborators including Helen Baghdoyan, Subimal Datta, and Jose Calvo. The role of aminergic neurones was established by the work of Ralph Lydic. Hobson and McCarley's discovery that both noradrenergic and serotonergic cells were active in waking but silent in REM was widely confirmed. Beginning in 1988, a formal analysis of dream content was pursued in eighteen studies conducted in collaboration with Robert Stickgold, Edward Pace-Schott, David Kahn, and others. This work has revealed that much of dream content was species (rather than individual) specific, leading to Hobson's theory of dreaming as a protoconscious state. Dr. Allan Hobson remains active in sleep and dream research since his closure of the MMHC lab in 2003 and his retirement in 2007. He is the Rupert Riedl Professor at the University of Vienna and holds visiting professor appointments in Lisbon, Naples, London, Milan, and Tuebingen. His current experimental collaboration is with Ursula Voss who studies the brain basis of lucid dreaming at the University of Frankfurt. |
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REM sleep and dreaming: towards a theory of protoconsciousness by J. Allan Hobson Abstract | Dreaming has fascinated and mystified humankind for ages: the bizarre and evanescent qualities of dreams have invited boundless speculation about their origin, meaning and purpose. For most of the twentieth century, scientific dream theories were mainly psychological. Since the discovery of rapid eye movement (REM) sleep, the neural underpinnings of dreaming have become increasingly well understood, and it is now possible to complement the details of these brain mechanisms with a theory of consciousness that is derived from the study of dreaming. The theory advanced here emphasizes data that suggest that REM sleep may constitute a protoconscious state, providing a virtual reality model of the world that is of functional use to the development and maintenance of waking consciousness. - from Nature Vol. 10, Nov. 2009 |
