Reflection 168: Edelman on Consciousness

December 29, 2009

(Copyright © 2009)

Gerald M. Edelman gives us fresh ways of looking at, talking about, understanding, and appreciating both consciousness and its brain. The importance of these contributions cannot be overestimated. Nor can the difficulty of gaining access to them through his writings. It helps if you have advanced degrees in molecular, cellular, and neural biology. It’s not that he doesn’t write well, it’s more that his radical concepts are couched in so unfamiliar a vocabulary as to require a great many encounters in different contexts before their meanings begin to accrete in solid understanding. He includes glossaries in several of his books, but the entries are so bare-boned that they often raise more questions than they answer.

I tried the total-immersion approach, reading seven books in succession (in order of copyright date, 1978 to 2004), hoping that enlightenment would eventually descend from the skies. Which, in the last three works, by dribs and drabs, it began to. It showed up first in unconscious intuitions I became aware of after waking from a sound sleep. I am not sure how they got into me, but there they’d be at three in the morning as I roused from a bout of REM dreaming. I’d understand things I hadn’t grasped before going to bed. Understand is not the right word. More I’d have a feel for an aspect of consciousness I’d never fully appreciated before. By the end of the eighth book, I could entertain elaborate thoughts and images pertaining to consciousness—again, early in the morning—that previously would have been beyond me, or over my head. I credit Edelman as the source of these new ways of apprehending my own mind, and myself for having the will to stay with his challenging program of thinking out loud in a series of books until he got it right in the seventh one.

I am now in the awkward position of learning from my self-imposed program of study, while not being able to recommend a similar course to anyone else because so much depends on the will, stamina, and hunger of the student. It takes a committed autodidact (self-directed learner) to follow Edelman as closely as he deserves. He is clearly an autodidact himself, and to paraphrase the familiar saying, it takes one to fully appreciate another. As perpetual learners, autodidacts typically lose interest in a program of study once they have absorbed or automatized it. They love grappling with novel aspects of consciousness, not mastery of the old and familiar. Self-respecting autodidacts never rest on their laurels. They are driven to reinvent themselves time and again throughout the course of their lives. Consider the career of William James at Harvard, first as physiologist, then psychologist, and finally as philosopher.

Which is similar to the history of Gerald M. Edelman, distinguished recipient of the Nobel Prize in Physiology or Medicine in 1972 for his work on the immune system. A molecular and cellular structuralist, he has contributed to the understanding of antibodies, proteins, plant mitogens, cell surfaces, and now the biology of human consciousness. His contributions in this last field center on his theory of neuronal group selection, which sheds light on the origins and workings of both the human nervous system and the mind it gives rise to in a manner consistent with Darwinian principles.

To put these remarks in perspective, I will digress somewhat in giving a brief history of my own self-directed learning. During high school, I read both Stendhal’s The Red and the Black and The Charterhouse of Parma on my own for reasons I can no longer remember. Both books spoke to my age and stage of development at the time. In college I put Crime and Punishment down as the sun was rising over the view of Harlem out the window, knowing I had been through a transformative experience. Ten years later, I stumbled on Thoreau’s Walden, which I don’t remember anyone recommending to me, and I went on to read almost every word he wrote, including, eventually, the two-volume Dover Journals. I still consider myself a late-blooming nineteenth-century man. Visual poet E.E. Cummings brought me into the twentieth century.  Later, in grad school, I spent two semesters with Sigmund Koch in a seminar reading one book, Personal Knowledge by Michael Polanyi. That was the most gripping, challenging, and rewarding course I ever had in school. I took it as an elective, so the motivation was my own. Polanyi’s theme is learning to tell the difference between knowledge and opinion so that you know how you know what you think you know.

Now it’s Gerald M. Edelman who particularly speaks to my age and stage of development in spite of the near ineffability of much he is writing about. He came to his topic (consciousness) from intense study of the immune system, bringing his terminology with him, and when there are no suitable terms, inventing his own. Which makes it hard going for those heading from other directions. But all along the way I have sensed he was theorizing about my personal consciousness as well as his own, so I stuck with him.

Now I am reading an eighth Edelman book, Second Nature: Brain Science and Human Knowledge (Yale University Press, 2006), which offers a summary of his theory of consciousness as a springboard to understanding human knowledge. The first four chapters offer an overview of his thinking on conscious-ness, leaving out details of the arduous, 28-year journey by which he derived it one step at a time. Here is how Edelman describes consciousness itself, the process he subsequently goes on to account for in theoretical terms:

In the awake conscious state, you experience a unitary scene composed variably of sensory responses—sight, sound, smell, and so on—as well as images, memories, feeling tones and emotions, a sense of willing or agency, a feeling of situatedness, and other aspects of awareness. Being conscious is a unitary experience in the sense that you cannot at any time become totally aware of just one thing to the complete exclusion of others. But you can direct your attention to various aspects of a less inclusive but still unitary scene. Within a short time, that scene will vary in one degree or another and, though still integrated, will become differentiated, yielding a new scene. The extraordinary fact is that the number of such privately experienced scenes is apparently limitless. The transitions seem to be conscious, and in their complete detail they are private, first-person subjective experiences (Second Nature, pages 13-14).

In the next sentence things get more complicated when he introduces the concept of intentionality: “Conscious states are often, but not always, about things or events, a property called intentionality” (page 14, my italics). And then goes on to summarize: “As human beings, we know what it is like to be conscious. Moreover, we are conscious of being conscious and can report on our experience” (page 14).

Which I think might lead some to oversimplify the nature of consciousness in that we frequently assume it is of some sort of world apart from ourselves, not recognizing it is the subjective doing of our own brains that underwrite the appearance in consciousness of any such world. To see something “with our own eyes” is no guarantee it actually happens as consciousness depicts it. Our minds are full of phantoms, vampires, ogres, aliens from other worlds, elves, Santas, and other characters we project onto the world as if they were not aspects of subjective consciousness and the bodies and brains which make it possible. It is a fundamental error to mistake phenomena in consciousness for the world as it is—for reality. The sounds of music and colors of art are in us, not the world, which in turn consists of sources, sinks, and patterns of energy that our brains and minds transform into the “objects and events” we are conscious of. It requires another indirect or imaginative transformation to locate them in an outer world.

It is good to remember that language and intentionality refer to concepts and appearances in consciousness, and these map onto the world very much as processes in the brain map onto consciousness. We live at least doubly removed from the so-called real world, so intentionality, in being “about things or events,” makes no claim that they actually exist in any other context than awareness itself. We know this from watching “movies” made from a succession of still images, and the many optical illusions and magic tricks that similarly “fool the eye.”

Which is my way of warning readers to beware of succinct distillations such as even Gerald Edelman might give of his work. When the unfamiliar terms crop up, as inevitably they must in writings about consciousness, we are asked to give the author the benefit of the doubt—particularly when the words flow easily and seem to make sense. Key terms in Edelman’s theory of neuronal group selection include reentry, degeneracy, perceptual categorization, global mappings, dynamic core, phenomenal transform, qualia, among others.

Reentry [to take one example] is the ongoing recur-sive interchange of parallel signals among brain areas, which serves to coordinate the activities of different brain areas in space and time. Unlike feed-back, reentry is not a sequential transmission of an error signal in a simple loop. Instead, it simulta-neously involves many parallel reciprocal paths and has no prescribed error function attached to it. (Wider than the Sky, 2004, pages 39-40).

As Edelman and Giulio Tononi detail “reentry” in an earlier work (A Universe of Consciousness, Basic Books, 2000):

Reentry plays the central role in our consciousness model, for it is reentry that assures the integration that is essential to the creation of a scene in primary consciousness. Integration can best be illustrated by considering exactly how functionally segregated maps in the cerebral cortex may operate coherently together even though there is no superordinate map or logically determined program. . . . The organi-zation of the cerebral cortex is such that even within a single modality, for example, vision, there is a multitude of specialized or functionally segregated maps devoted to different submodalities—color, movement, and form. Despite this diversity, we are aware of a coherent perceptual scene. When we see such a scene, we are not aware of colors, move-ments, and forms separately and independently, but bind the color with the shape and the movement into recognizable objects. Our ability to act coher-ently in the presence of diverse, often conflicting, sensory stimuli requires a process of neural inter-action across many levels of organization without any superordinate map to guide the process. This is the so-called binding problem: How can a set of diverse and functionally segregated maps cohere without a higher-order controller? . . . Binding can occur as a result of reentry across brain maps that establishes short-term temporal correlations and synchrony among the activities of widely spaced neuronal groups in different maps. As a result, neurons in these groups fire at the same time. Thus, reentry correlates a large number of dynamic circuits in space and time. . . . This binding principle, made possible by reentry, is repeated across many levels of brain organization and plays a central role in mechanisms leading to consciousness (pages 106-107).

The tradeoffs between explicit details and broad summations in the different works of Gerald M. Edelman makes it difficult to recommend one particular work as representing his thought in its most cogent form. To those highly motivated to under-stand consciousness, I can at best recommend a selection of three of Edelman’s books:

Edelman, Gerald M. and Giulio Tononi, A Universe of Consciousness: How Matter Becomes Imagina-tion (Basic Books, 2000). This work assembles in readable form the details on which the theory of neuronal group selection rests.

Edelman, Gerald M., Wider Than the Sky: The Phenomenal Gift of Consciousness (Yale University Press, 2004). This summary presents the theory in its clearest form.

Edelman, Gerald M., Second Nature: Brain Science and Human Knowledge (Yale University Press, 2006). The theory is here applied to gain fresh insight into the issue of human knowledge.

I strongly urge any readers with the will to do so to read them in the order given, from detailed account to more general overview. Five other books I have read in addition to those listed above:

Edelman, Gerald M. and Vernon B. Mountcastle, The Mindful Brain: Cortical Organization and the Group-Selective Theory of Higher Brain Function (The MIT Press, 1978; reprinted 1982).

Edelman, Gerald M., Topobiology: An Introduction to Molecular Embryology (HarperCollins Publishers, Basic Books, 1988).

Edelman, Gerald M., The Remembered Present: A Biological theory of Consciousness (Basic Books, 1989).

Edelman, Gerald M., Bright Air, Brilliant fire: On the Matter of Mind (Basic Books, 1992).

Edelman, Gerald M., and Jean-Pierre Changeux, editors, The Brain (Transaction Publishers, 2001).

I have yet to read:

Edelman, Gerald M., Neural Darwinism: The Theory of Neuronal Group Selection (Basic Books, 1987).

Medial View of Brain-96

 

 

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