Roger Wolcott Sperry: Wikis

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Roger Wolcott Sperry
Born August 20, 1913 (1913-08-20)
Hartford, Connecticut
Died April 17, 1994 (1994-04-18)
Fields neuropsychologist
Alma mater Oberlin College, University of Chicago
Doctoral advisor Paul A. Weiss
Known for split-brain research
Notable awards 1981 Nobel Prize in Medicine

Roger Wolcott Sperry (August 20, 1913 – April 17, 1994) was a neuropsychologist, neurobiologist and Nobel laureate who, together with David Hunter Hubel and Torsten Nils Wiesel, won the 1981 Nobel Prize in Medicine for his work with split-brain research.

Sperry was born in Hartford, Connecticut, to Francis Bushnell and Florence Kraemer Sperry. His father was in banking, and his mother trained in business school. Roger had one brother, Russell Loomis. Their father died when Roger was 11. Afterwards, his mother became assistant to the principal in the local high school.

Sperry went to Hall High School in West Hartford, Connecticut, where he was a star athlete in several sports, and did well enough academically to win a scholarship to Oberlin College. At Oberlin, he was captain of the basketball team, and he also took part in varsity baseball, football, and track; he received his bachelor's degree in English in 1935 and a master's degree in psychology in 1937. He received his Ph.D. in zoology from the University of Chicago in 1941, supervised by Paul A. Weiss. Sperry then did post-doctoral research with Karl Lashley at Harvard University.

In 1942, he began work at the Yerkes Laboratories of Primate Biology, then a part of Harvard University. He left in 1946 to become an assistant professor, and later associate professor, at the University of Chicago. In 1952, he became the Section Chief of Neurological Diseases and Blindness at the National Institutes of Health. In 1954, he accepted a position as a professor at the California Institute of Technology (Caltech) where he performed his most famous experiments with his then student Michael Gazzaniga.

Before Sperry's experiments, some research evidence seemed to indicate that areas of the brain were largely undifferentiated and interchangeable. In his early experiments, Sperry showed that the opposite was true: after early development, circuits of the brain are largely hardwired.

In his Nobel-winning work, Sperry tested ten patients who had undergone an operation developed in 1940 by William Van Wagenen, a neurosurgeon in Rochester, NY [1]. The surgery, designed to treat epileptics with intractable grand mal seizures, involves severing the corpus callosum, the area of the brain used to transfer signals between the right and left hemispheres. Sperry and his colleagues tested these patients with tasks that were known to be dependent on specific hemispheres of the brain and demonstrated that the two halves of the brain may each contain consciousness. In his words, each hemisphere is

indeed a conscious system in its own right, perceiving, thinking, remembering, reasoning, willing, and emoting, all at a characteristically human level, and . . . both the left and the right hemisphere may be conscious simultaneously in different, even in mutually conflicting, mental experiences that run along in parallel
Roger Wolcott Sperry , 1974

This research contributed greatly to understanding the lateralization of brain function. In 1989, Sperry also received the National Medal of Science.

In addition to his contribution in establishing the lateralized function of the brain, Sperry is also noted for his chemo affinity theory, which has been not only influential in formation of testable hypotheses in how precise neuronal wiring diagram is established in the brain, but the hypothesis itself has been verified by numerous experiments.

"The cells and fibers of the brain must carry some kind of individual identification tags, presumably cytochemical in nature, by which they are distinguished one from another almost, in many regions, to the level of the single neurons"
Roger Wolcott Sperry

In the words of a 2009 review article in Science magazine: "He suggested that gradients of such identification tags on retinal neurons and on the target cells in the brain coordinately guide the orderly projection of millions of developing retinal axons. This idea was supported by the identification and genetic analysis of axon guidance molecules, including those that direct development of the vertebrate visual system."

In 1949, Sperry married Norma Gay Deupree. They had one son, Glenn Michael, and one daughter, Janeth Hope. At the time he received the Nobel Prize, he was suffering from advanced stage Kuru. He had acquired the disease as a young neuroscientist through contact with some of the human brains he was using for his research.

Bibliography

  • "The problem of central nervous reorganization after nerve regeneration and muscle transposition." Quart. Rev. Biol. 20: 311-369 (1945)
  • "Regulative factors in the orderly growth of neural circuits." Growth Symp. 10: 63-67 (1951)
  • "Cerebral organization and behavior." Science 133: 1749-1757 (1961)
  • "Chemoaffinity in the orderly growth of nerve fiber patterns and connections." Proc. Nat. Acad. Sci. USA 50: 703-710 (1963)
  • "Interhemispheric relationships: the neocortical commissures; syndromes of hemisphere disconnection." (with M.S. Gazzaniga, and J.E. Bogen) In: P. J. Vinken and G.W. Bruyn (Eds.), Handbook Clin. Neurol (Amsterdam: North-Holland Publishing Co.) 4: 273-290 (1969)
  • "Lateral specialization in the surgically separated hemispheres." In: F. Schmitt and F. Worden (Eds.), Third Neurosciences Study Program (Cambridge: MIT Press) 3: 5-19 (1974)
  • "Mind-brain interaction: mentalism, yes; dualism, no." Neuroscience 5: 195-206. Reprinted in: A.D. Smith, R. Llanas and P.G. Kostyuk (Eds.), Commentaries in the Neurosciences (Oxford: Pergamon Press) pp. 651-662 (1980)
  • "Science and moral priority: merging mind, brain and human values." Convergence, Vol. 4 (Ser. ed. Ruth Anshen) New York: Columbia University Press (1982)

References

  1. ^ Gazzangiga, M. F. (2008). Human: The Science Behind What Makes Us Unique. HarperCollins Publishers.
  • Bogen, J E (September 1999). "Roger Wolcott Sperry (20 August 1913-17 April 1994)". Proceedings of the American Philosophical Society 143 (3): 491–500. PMID 11624452.  
  • Hamilton, C R (October 1998). "Paths in the brain, actions of the mind: Special issue in honor of Roger W. Sperry". Neuropsychologia 36 (10): 953–4. PMID 9845044.  
  • Voneida, T J (1997). "Roger Wolcott Sperry, 20 August 1913-17 April 1994". Biographical memoirs of fellows of the Royal Society. Royal Society (Great Britain) 43: 461–70. PMID 11619982.  
  • Miller, J G (October 1994). "Roger Wolcott Sperry. Born August 20, 1913--died April 17, 1994". Behavioral science 39 (4): 265–7. doi:10.1002/bs.3830390402. PMID 7980367.  
  • Trevarthen, C (October 1994). "Roger W. Sperry (1913-1994)". Trends Neurosci. 17 (10): 402–4. doi:10.1016/0166-2236(94)90012-4. PMID 7530876.  
  • Hubel, D (May 1994). "Roger W. Sperry (1913-1994)". Nature 369 (6477): 186. doi:10.1038/369186a0. PMID 8183336.  
  • Girstenbrey, W (December 1981). "[The different faces of the hemispheres. The presentation of the Nobel Prize for Medicine and Physiology 1981 to the neurobiologists Sperry, Hubel and Wiesel]". Fortschr. Med. 99 (47-48): 1978–82. PMID 7035316.  
  • Ottoson, D (October 1981). "[Sperry has given us a new dimension on views of the higher functions of the brain]". Lakartidningen 78 (43): 3765–73. PMID 7033697.  

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Quotes

Up to date as of January 14, 2010

From Wikiquote

Futurists and common sense concur that a substantial change, worldwide, in life style and moral guidelines will soon become an absolute necessity.

Roger Wolcott Sperry (20 August 1913 - 17 April 1994) was a neuropsychologist, neurobiologist and pioneer in the sciences of consciousness who, together with David H. Hubel and Torsten Wiesel, won the 1981 Nobel Prize in Medicine, for his independent work in split-brain research.

Contents

Sourced

Prior to the advent of brain, there was no color and no sound in the universe, nor was there any flavor or aroma and probably rather little sense and no feeling or emotion.
There probably is no more important quest in all science than the attempt to understand those very particular events in evolution by which brains worked out that special trick that has enabled them to add to the cosmic scheme of things: color, sound, pain, pleasure, and all the other facets of mental experience.
To see a promising solution to a dilemma and then just leave it to questionable development at its own pace without trying to aid its implementation would seem a dereliction.
The centermost processes of the brain with which consciousness is presumably associated are simply not understood. They are so far beyond our comprehension that no one I know of has been able to imagine their nature.
  • The objective psychologist, hoping to get at the physiological side of behavior, is apt to plunge immediately into neurology trying to correlate brain activity with modes of experience ... The result in many cases only accentuates the gap between the total experience as studied by the psychologist and neural activity as analyzed by the neurologist.
    • "Action Current Study in Movement Coordination" in Journal of General Psychology (1939)
  • I have never been entirely satisfied with the materialistic or behavioristic thesis that a complete explanation of brain function is possible in purely objective terms with no reference whatever to subjective experience; i.e., that in scientific analysis we can confidently and advantageously disregard the subjective properties of the brain process. I do not mean we should abandon the objective approach or repeat the errors of the earlier introspective era. It is just that I find it difficult to believe that the sensations and other subjective experiences per se serve no function, have no operational value and no place in our working models of the brain.
  • Prior to the advent of brain, there was no color and no sound in the universe, nor was there any flavor or aroma and probably rather little sense and no feeling or emotion. Before brains the universe was also free of pain and anxiety.
    • "Evolution of the Human Brain" (1964), p. 2
  • There probably is no more important quest in all science than the attempt to understand those very particular events in evolution by which brains worked out that special trick that has enabled them to add to the cosmic scheme of things: color, sound, pain, pleasure, and all the other facets of mental experience.
    • "Evolution of the Human Brain" (1964), p. 3
  • Any model or description that leaves out conscious forces ... is bound to be sadly incomplete and unsatisfactory ... This scheme is one that puts mind back over matter, in a sense, not under or outside or beside it. It is a scheme that idealizes ideas and ideals over physical and chemical interactions, nerve impulse traffic, and DNA. It is a brain model in which conscious mental psychic forces are recognized to be the crowning achievement of some five hundred million years or more of evolution.
    • Mind, Brain, and Humanist Values (1965)
  • Futurists and common sense concur that a substantial change, worldwide, in life style and moral guidelines will soon become an absolute necessity.
  • It is mutual fear and distrust that mostly generate world tensions and these can be traced in no small measure, like other root causes of worsening world conditions, to different people's conflicting and often intolerant, value-belief differences ... Whereas in the past science did little, if anything, to remedy this situation and in some ways made things worse, our reformed "macro-determinist" science that includes consciousness and subjective values ... provides common universal ethical foundations on which all nations could work to build a World Government or at least a World Security System to help control nuclear developments and other global threats that require international collaboration.
    • The Human Predicament: A Way Out? (1985), p. 3
  • To see a promising solution to a dilemma and then just leave it to questionable development at its own pace without trying to aid its implementation would seem a dereliction.
    • The Human Predicament: A Way Out? (1985), p. 4
  • The time has passed when nations should be allowed to do as they individually wish with regard to global matters, each striving solely in its own interests, with the more powerful now able to destroy all humanity and more.
    For the common good, we need to frame and abide by a higher system of law and justice, designed with less national, more godlike, perspectives for the preservation and welfare of the biosphere as a whole.
    The problems of setting up and administering an effective, international force of this kind can hardly be more grave, formidable or insoluble than those we encounter on any alternative course.
    • Toward a Higher System of World Law and Justice (1986)
  • The centermost processes of the brain with which consciousness is presumably associated are simply not understood. They are so far beyond our comprehension that no one I know of has been able to imagine their nature.
    • As quoted in Genius Talk : Conversations with Nobel Scientists and Other Luminaries (1995) by Denis Brian ISBN 0306450895

Science and the Problem of Values (1972)

The world we live in is driven not solely by mindless physical forces but, more crucially, by subjective human values. Human values become the underlying key to world change.
  • It seems important that the social value factor be more generally recognized as a powerful causal agent in its own right and something to be dealt with directly as such. No more critical task can be projected for the 1970s than that of seeking for civilized society a new, elevated set of value guidelines more suited to man's expanded numbers and new powers over nature, a frame of reference for value priorities that will act to secure and conserve our world instead of destroying it.
    • p.119
  • The grand design of nature perceived broadly in four dimensions, including the forces that move the universe and created man, with special focus on evolution in our own biosphere, is something intrinsically good that it is right to preserve and enhance, and wrong to destroy and degrade.
    • p. 127
  • The upward thrust of evolution as part of the design becomes something to preserve and revere.
    • p. 128
  • The new way of thinking, spawned by the cognitive revolution, shows strong promise ... Reversing previous doctrine in science, the new paradigm affirms that the world we live in is driven not solely by mindless physical forces but, more crucially, by subjective human values. Human values become the underlying key to world change.

Nobel lecture (1981)

"Some Effects of Disconnecting the Cerebral Hemispheres" (8 December 1981)
Where there used to be a chasm and irreconcilable conflict between the scientific and the traditional humanistic views of man and the world, we now perceive a continuum. A unifying new interpretative framework emerges with far reaching impact not only for science but for those ultimate value-belief guidelines by which mankind has tried to live and find meaning.
  • With few exceptions, the bulk of the collected lesion evidence up through the 1950s into the early '60s converged to support the picture of a leading, more highly evolved and intellectual left hemisphere and a relatively retarded right hemisphere that by contrast, in the typical righthander brain, is not only mute and agraphic but also dyslexic, word-deaf and apraxic, and lacking generally in higher cognitive function.
  • Earlier contentions that the right hemisphere is not even conscious largely gave way by the mid seventies to an intermediate position conceding that the mute hemisphere may be conscious at some lower elemental levels, but claiming that it lacks the higher, reflective, self-conscious kind of inner awareness that is special to the human mind and is needed, so it is said, to qualify the right conscious system as a "self' or "person". Self awareness in particular is reported, on the basis of mirror tests mainly, to be a predominantly human attribute and is rated by developmental as well as by evolutionary standards to be a highly advanced phase of conscious awareness.
  • Unlike other aspects of cognitive function, emotions have never been readily confinable to one hemisphere. Though generated by lateralized input, the emotional effects tend to spread rapidly to involve both hemispheres, apparently through crossed fiber systems in the undivided brain stem.
  • One of the more important things to come out of the split-brain work, as an indirect spin-off, is a revised concept of the nature of consciousness and its fundamental relation to brain processing. The key development here is a switch from prior non-causal, parallelist views to a new causal, or "interactionist" interpretation that ascribes to inner experience an integral causal control role in brain function and behavior. In effect, and without resorting to dualist views, the mental forces and properties of the conscious mind are restored to the brain of objective science from which they had long been excluded on materialist-behaviorist principles.
  • Cognitive introspective psychology and related cognitive science can no longer be ignored experimentally, or written off as "a science of epiphenomena", nor either as something that must, in principle, reduce eventually to neurophysiology. The events of inner experience, as emergent properties of brain processes, become themselves explanatory causal constructs in their own right, interacting at their own level with their own laws and dynamics. The whole world of inner experience (the world of the humanities) long rejected by 20th century scientific materialism, thus becomes recognized and included within the domain of science.
  • The former scope of science, its limitations, world perspectives, views of human nature, and its societal role as an intellectual, cultural and moral force all undergo profound change. Where there used to be a chasm and irreconcilable conflict between the scientific and the traditional humanistic views of man and the world, we now perceive a continuum. A unifying new interpretative framework emerges with far reaching impact not only for science but for those ultimate value-belief guidelines by which mankind has tried to live and find meaning.

New Mindset on Consciousness (1987)

Sunrise magazine (December 1987/January 1988)
Science traditionally takes the reductionist approach, saying that the collective properties of molecules, or the fundamental units of whatever system you're talking about, are enough to account for all of the system's activity. But this standard approach leaves out one very important additional factor, and that's the spacing and timing of activity — its pattern or form.
What is needed to break the vicious spiral is a world-wide change in attitudes, values, and social policy.
Instead of maintaining the traditional separation of science and values, cognitive theory says the two come together in brain function.
Science no longer upholds a value-empty existence, in which everything, including the human mind, is driven entirely by strictly physical forces of the most elemental kind.
  • As a brain researcher, I'd started out simply accepting the strictly objective principles of the behaviorist position. In the 1950s and early 1960s, all respectable neuroscientists thought in these terms. In those days, we wouldn't have been caught dead implying that consciousness or subjective experience can affect physical brain processing.
    My first break with this thinking — although I certainly didn't see it that way at the time — came in a 1952 discussion of mind-brain theory in which I proposed a fundamentally new way of looking at consciousness. In it, I suggested that when we focus consciously on an object — and create a mental image for example — it's not because the brain pattern is a copy or neural representation of the perceived object, but because the brain experiences a special kind of interaction with that object, preparing the brain to deal with it.
    I maintained that an identical feeling or thought on two separate occasions did not necessarily involve the identical nerve cells each time. Instead, it is the operational impact of the neural activity pattern as a whole that counts, and this depends on context — just as the word "lead" can mean different things, depending on the rest of the sentence.
  • When the brain is whole, the unified consciousness of the left and right hemispheres adds up to more than the individual properties of the separate hemispheres.
  • Science traditionally takes the reductionist approach, saying that the collective properties of molecules, or the fundamental units of whatever system you're talking about, are enough to account for all of the system's activity. But this standard approach leaves out one very important additional factor, and that's the spacing and timing of activity — its pattern or form. The components of any system are linked up in different ways, and these possible relationships, especially at the higher levels, are not completely covered by the physical laws for the elementary interactions between atoms and molecules. At some point, the higher properties of the whole begin to take over and govern the fate of its constituents.
    A simple way to illustrate this idea is to imagine a molecule in an airplane flying from L.A. to New York. The molecule may be jostled somewhat or held in position by its neighbors, but these lower-level actions are trivial compared to its movement as the plane flies across the continent. If you plot the movement of the molecule through time and space, those features governed by the higher properties of the plane as a whole make those controlled at the level of the molecule insignificant by comparison. The higher properties control the lower, not by direct intervention, but by supervention.
  • I have a very one-track mind that needs to concentrate. I asked myself which issue is more important: whether mental states are more left- or right-hemispheric, or whether they are causal in brain function. From weighing the pros and cons, I decided that the left-brain, right-brain work was well in orbit and that it would be more important to shift my primary focus to consciousness.
    The mind-brain issues are intrinsically more compelling. They carry strong humanistic as well as scientific implications. I could foresee changes in our world view, guiding beliefs, and social values. In the context of today's worsening world conditions and our imperiled future, this work seemed far more important than whether you can find a brain theory enabling people to learn faster, draw better, make better medical diagnoses, and so on.
    We're beginning to learn the hard way that today's global ills are not cured by more and more science and technology.
  • What is needed to break the vicious spiral is a world-wide change in attitudes, values, and social policy. As Einstein put it, "We need a substantially new manner of thinking if mankind is to survive."
  • Instead of maintaining the traditional separation of science and values, cognitive theory says the two come together in brain function. If we are correct in saying that our conscious mental values not only arise from, but also influence brain processing, then it becomes possible to integrate values with the physical world on a scientific rather than supernatural basis. It's been the traditional role of religion to affirm the primary importance of our higher values in this world by invoking a supreme power. In cognitivism, it is science that affirms the powerful controlling role of higher values, and it is able to do so on grounds that are verifiable — that is, testable against reality as it really is.
    On these new terms, science no longer upholds a value-empty existence, in which everything, including the human mind, is driven entirely by strictly physical forces of the most elemental kind. We get a vastly revised answer to the old question "What does science leave to believe in?" that gives us a different image of science and the kind of truth science stands for. This new outlook leads to realistic, this world values that provide a strong moral basis for environmentalism and population controls and for policies that would protect the long-term evolving quality of the biosphere.
  • Cognitivism bridges the chasm between what the writer C. P. Snow has called the "two cultures" — the widening gap between the world view of the scientist and the humanist. The Caltech philosopher W. T. Jones has called this the crisis of contemporary culture.
  • I think time will show that the new approach, emphasizing emergent "macro" control, is equally valid in all the physical sciences, and that the behavioral and cognitive disciplines are leading the way to a more valid framework for all science. Although the theoretic changes make little difference in physics, chemistry, molecular biology, and so on, they are crucial for the behavioral, social, and human sciences. They don't change the analytic, reductive methodology, just the interpretations and conclusions. There seems little to lose, and much to gain.

Quotes about Sperry

  • Sperry's thinking about subjective experience, consciousness, the mind, and human values makes a powerful plea for a new scientific examination of ethics in the workings of consciousness. These ideas were crystallized in his paper "The Impact and Promise of the Cognitive Revolution" (1993).
    • Theodore J. Voneida in the National Academy of Sciences Biographical Memoirs V.71 (1997), p. 326
  • The impact of Sperry's philosophy, similar to that of his scientific discoveries previously, has now transcended the boundaries of science and reaches into human awareness worldwide. Dr. Robert Muller, former Assistant Secretary General of the United Nations, for instance, is deeply impressed by, and actively promotes, Sperry's work — He fully recognizes the significance of the neuroscientist's theory of emergence and downward causation, which transcends dualism and reductionism, leads in an unbroken continuum from atoms to subjective experience, and describes each newly emergent phenomenon in the universe as an entity in its own right with laws and properties that never before existed. Such new emergents (which disappear in reductionist thinking) affect everything else on earth, including the elements that created them (downward causation) but most importantly the future quality of evolution. Values, thus — as emergents of brain function — are recognized as the most powerful determinants on earth, even in the world of science.

Unsourced

  • 90% of our brain's energy is used for posture alone.

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