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CURRENT BIOGRAPHY January 1986

reshaping scientists' view of the organization of the central ner\-ous system (CNS). Previously, scien• tists had believed that the connections of the ner• vous system were ven,- precise and had to be properly "wired" to correctly; but when Weiss surgically crossed nerve connections, no dif• ference in the subject's was detected. As Sperry explained in PeopJe (February' 5, 1979), Weiss and others therefore concluded "that function was infinitely malleable and that a nerve would connect as readily to one place as another, like the wiring of a house." Through experience, then, the brain and spina] cord learned to sort out the nerves' impulses to regulate behavior: the form and function of the nervous system were not pre• determined by . Testing Weiss's findings in experiments of his own. Sperry surgically crossed the nerves control• ling the muscles of the hind legs in a rat. Eventually each nerve would have been "reeducated" to con• trol the leg muscle to which it had been newly con• nected. Surprisingly, the expected reeducation did not occur even after an extended period of time: when, for example, the left hind foot was stimu• Sperry, Roger W(olcott) lated, the right foot always responded. Sperry de• tailed his experiments, which shattered Weiss's Aug. 20, 1913- PsychobiologJst. Address: b. theory, in his doctoral dissertation, "Functional re• California Institute of Technology, Division of sults of crossing nerves and transposing muscles in Biology, 156-29, Pasadena, Calif. 91125 the fore and hind limbs of the rat," on completion of which in 1941 the University of Chicago award• One of the major forces behind contemporary re• ed him a Ph.D. degree in zoology, search into the mysteries of the brain is Using because their nervous sys• Roger W. Sperry, the Hixon Professor of Ps>'chobi- tems are capable of regeneration, Sperry next ology at the California Institute of Technology. out to discover by what means the nerves are guid• Sperry, who helped to pioneer basic of ed to the correct connection site or "target cell." In contemporary during the 1940s, initi• one experiment, he rotated the eyeball of a frog ated "split-brain" studies in beginning in and cut its optic nerve. Although during the healing the early 1960s after engaging for several years in process the nerve fibers became hopelessly tan• similar research on . Contradicting long• gled and enmeshed in the scar, the regenerated standing behefs about the functioning of the brain, nerve overcame that obstacle and ignored the re• Sperry's demonstrated that while in most positioning of the eyeball to reattach itself correct• people the brain's left hemisphere is indeed domi• ly. From those and similar experiments, in about nant for verbal and analytical tasks the right hemi• 1940 Sperry brilliantly derived the theory of sphere is also capable of learning and "chemospecificity," or "chemoaffinity." According communicating and is generally dominant in spa• to that theory, which Sperry delineated in papers tial tasks and music. For his fundamental contribu• published during the next twenty years, animals in tion to the , affecting embryo develop with highly specific func• the entwined fields of psychology, neurology, and tions, which are differentiated during the growth biolog>', Sperr\ was one of the recipients of the process according to their genetically predeter• 1981 Nobel Prize in Physiology' or Medicine. mined chemical composition. Thus motor and sen• sory nerve cells are distinguished from those The son of Francis Bushnell Sperry and Flor• serving such organs as the heart, lungs, and gastro• ence (Kraemer] Sperry, was intestinal tract. born on August 20, 1913 in Hartford, Connecticut and received his elementary and high-school edu• Even greater specificity is provided by the actual cation nearby, in Elmwood and West Hartford. site that the neurons are destined to serve. As Sper• Awarded a four-year Amos C. Miller scholarship ry explained in "The Growth of Nerve Circuits," in 1931 to attend Oberlin College in Ohio, Sperry which was published in the November 1959 issue played varsity baseball and football, was on the of Scientific American, the skin, for example, may track team, and captained the basketball squad in be assumed to undergo "a highly refined differen• addition to studying for an A.B. degree in English, tiation until each spot on the skin acquires a unique which Oberlin granted him in 1935. Intrigued, chemical makeup." A , then, can only con• however, by his undergraduate psychologj' courses nect with a site that has the same chemical "label," with R. H. Stetson, an internationally recognized that is, one with which it has a "chemoaffinity." authority on the physiology of speech, and L. E. The mechanism of chemoaffinity accorded well Cole, Sperry decided to pursue that subject rather with the way other body systems were known to than continue his humanistic studies. After spend• develop, and Sperry predicted that it would be ing two years as a graduate assistant to Stetson, found to govern the development of every form of who emphasized the biological aspects of psychol• response, "from the simplest reflex to the most ogy, he was granted an M.A. degree in psychology complicated patterns of inherited behavior." by Oberlin in 1937. Sperry's experimental and theoretical work on chemoaffinity not only explained how the organi• By that time, Sperry's main interest lay in the zation of neural networks for behavior could be in• formation of neuronal circuitry and its relation to herited and develop into a brain, but also opened the higher functions of the brain, such as , up a wide range of new avenues of scientific inves• learning, and . Accordingly, he went to tigation into the brain and behavior. Even forty the University of Chicago specifically to study un• years after he first postulated the theory, it was der the brilliant Austrian-born biologist Paul Al- "still at the center of current neurobiological fred Weiss, whose "resonance principle" was work," according to the estimate of his colleasnje by the right brain. When asked to identify the pic• Sperry explained in his Nobel address, "cognitive ture, the subject could not do so verbally because introspective psychology and related cognitive sci• the left hemisphere, which controls speech, had no ence can no longer be ignored experimental• access to that information; however, with his left ly. .. . The whole world of inner experience (the hand, the subject reached behind a screen, world of the humanities], long rejected by 20th- searched through a pile of miscellaneous objects, century scientific materialism, thus becomes recog• and correctly selected the scissors. When asked nized and included within the domain of science." how he picked the correct object, the subject insist• Furthermore, in addition to being legitimate ob• ed it was only by chance. "No one," Gazzaniga re• jects of scientific scrutiny as causes, as well as counted in Science (October 30, 1981), "was emergent properties, of brain activities, conscious• prepared for the riveting experience of observing ness, free will, and values—traditionally restricted a split-brain patient^enerating integrated activities to the domains of theology and philosophy—are with the mute right hemisphere that the language- also subject to modification through dominant left hemisphere was unable to describe gained by science. Science and religion, then, or comprehend. That was the sweetest afternoon." would be partners in a search for a new global eth• Further experimentation conclusively proved ic that would reshape man's values and, conse• not only that the right hemisphere was superior to quently, change his behavior. In that possibility, the left hemisphere in such areas as musical abili• Sperry sees the best hope for the survival of the hu• ty, reading faces, and sorting sizes and shapes, but man race. His theory is explained in depth in that it evinced considerable social understanding Science and MoraJ Priority, a collection of his es• and self-. Sperry's findings verified that says and lectures, which was published in 1983 by new and entirely unforeseen importance had to be Columbia University Press. accorded the right hemisphere of the brain. The many honors Sperry has received include First described in papers published in the late the Warren Medal of 1960s, Sperry's split-brain research was quickly (1969), an award for distinguished scientific contri• recognized as epochal. Because Sperry's findings butions from the American Psychological Associa• had important clinical implications, including pos• tion (1971), the Passano Award for Medical sible treatments for mental or psychosomatic dis• Research (1973), and the Wolf Foundation Prize in eases, he was honored in 1979 with the most Medicine (1979). He has also been awarded honor• prestigious prize in American medicine, the Albert ary degrees by Cambridge University, the Univer• Lasker Basic Medical Research Award, which car• sity of Chicago, Rockefeller University, Oberlin ried with it a $15,000 premium. Two years later his College, and other institutions. Elected to the Na• achievement earned him the Nobel Prize in Physi• tional Academy of Sciences in 1960, he is a Fellow ology or Medicine, which he shared with two other of the Royal Society of Great Britain and also be• brain researchers, Torsten N. Wiesel and David H. longs to the American Academy of Arts and Sci• Hubel, both of Harvard University. In awarding ences, the American Philosophical Society, the him that prize, the Royal Swedish Academy of Sci• Pontifical Academy of Sciences, and many other ences commended Sperry for "extracting the se• societies and groups. In 1972 he was honored as crets from both hemispheres of the brain and California Scientist of the Year. demonstrating that they are highly specialized and Described by Yvonne Baskin in Omni (August also that many higher functions are centered in the 1983) as "bearded, with bullet eyes capped by right hemisphere." gracefully arched brows," Roger Wolcott Sperry By no means unaware of the prospective impor• has been married since December 28,1949 to Nor• tance of those discoveries for a theory of , ma Gay Deupree. They have two children, Glenn Sperry suggested in his Nobel prize lecture, pub- Tad and Jan Hope. His hobbies include sculpting hshed in Science (September 24, 1982), that "one and figure drawing, ceramics, folk dancing, and beneficial outcome that appears to hold up is an paleontology. Although an "intensely private" enhanced awareness, in and elsewhere, man, according to Yvonne Baskin, he is by no of the important role of the nonverbal components means lacking in a sense of humor: he once accept• and forms of the intellect." In addition, his split- ed an award by saying, "The great and brain research had led him to reject conventional feeling in my right brain is more than my left brain dualist thinking about mind and brain. Never a can find the words to tell you," "reductionist," by the mid-1960s Sperry was al• ready developing a theory of mind-brain interac• tion that held that was more than just a product of brain circuitry; it was also a prop• References; Engineering & Science p6-*- N '81 erty of mind that, although reducible to neither its por; N Y Times p50 O 10 '81; Omni p68+Ag '83 physical nor chemical components, influenced por; Science 214:517+ O 30 '81 por; Trends in physical and chemical events in the brain as much isieuroscience p222+ Jl '82; International Who's as, if not more than, it was influenced by them. Who, 1985-86; McGraw Hili Modern Men of That notion, which Sperry termed mentalism, was Science vol 2 [1968]; Who's Who in America, supported by the split-brain studies. As a result, as 1984-85; World Who's Who in Science (1968J