Saturday, June 27, 2009

Self Model & World Model

Most of us go through life pretty much assuming that what we “are” is evident (I am that which perceives, acts, feels and makes my own decisions), and that what the world “is” is also evident (the world is that which I perceive “out there”—land, trees, water, sky, mountains, buildings, animals, other people, objects).  Now along comes a book by Thomas Metzinger, The Ego Tunnel, (Basic Books: 2009) which, basing itself on the neuroscientific studies of recent years, turns these “obvious” assumptions upside down. It turns out, according to philosopher Metzinger, that what we “are” and what the world “is” are both based on models conjured up by the brain.  We each have what Metzinger calls a “phenomenal self model” (PSM)—the conscious model of our organism as a whole that is activated by the brain. As for the world “out there,” it is also a model fed to us by our limited sensory equipment (eyes, ears, nose, taste, touch) and processed by our brains into “a low-dimensional projection of the inconceivably richer physical reality surrounding us and sustaining us.”  So consciousness, for Metzinger and neuroscience, takes place in two related and interrelated steps: “First, our brains generate a world-simulation, so perfect that we do not recognize it as an image in our minds.” This specific world-simulation has been refined over evolutionary time to provide us with precisely what we need to survive. Then, “they [i.e. our brains] generate an inner image of ourselves as a whole.” This latter is the phenomenal Ego—the internal image of the person-as-a-whole, as it appears in conscious experience. Neither one of these models puts us “in direct contact with outside reality or with ourselves.”  But since we are essentially blind to the fact that both are models, we have the experience of “seeing” reality and being ourselves fully and completely in that real world. This is what Metzinger means by the Ego Tunnel of his title: far from realizing that we are perceiving models created by our brain cells, we are in a kind of tunnel that totally precludes us from realizing this. It is only scientific experiments done in collaboration (to get beyond the tunnel that keeps each individual blind) that provide us with evidence of this counter-intuitive situation. (We should always remind ourselves that the earth as a globe spinning in inconceivably vast space was also counter-intuitive for most of human history.)

            The first experiment Metzinger describes is one done in 1998 by University of Pittsburgh psychiatrists Matthew Botvinick and Jonathan Cohen. It’s a kind of play on the oft-reported phenomenon of the phantom limb, where patients who have had an arm or leg removed persist in “feeling” sensation in the absent limb. Botvinick and Cohen contrived a kind of obverse experiment:

            “Subjects observed a rubber hand lying on the desk in front of them, with their own corresponding hand concealed from their view by a screen. The visible rubber hand and the subject’s unseen hand were then synchronously stroked with a probe. After a certain time (a mere 60 to 90 seconds when Metzinger tried this himself), the famous rubber-hand illusion emerges. Suddenly, you experience the rubber hand as your own, and you feel the repeated strokes in this rubber hand. Moreover, you feel a full-blown “virtual arm”—that is a connection from your shoulder to the fake hand on the table in front of you.” (p. 3)

The lessons of the rubber-hand experiment, as well as the later out-of-body experiences and experiments Metzinger describes, are profound. For in these situations, the existence and malleability of the PSM or phenomenal self-model, as a model, comes to light.  Our brain, that is, creates a model of our bodies that is usually very accurate and immensely useful. But it can be fooled, as it is in the rubber hand experiment, into thinking that a rubber hand is part of itself.  Therefore, we come to understand that what we consciously think of as “me,” is really only a model conjured by the brain. We also see that it can be manipulated in such a way that a rubber hand (a fake me) becomes a part of “me,” becomes “mine,” with feelings and sensations. Metzinger then poses a startling question: “Could one create a full-body analog of the rubber-hand illusion? Could the entire self be transposed to a location outside of the body?” (Normally, we think of our “self” as residing somewhere inside our heads.)

            His answer is “yes.” In out-of-the-body experiences (OBEs), which Metzinger himself has had (and which Olaf Blanke, a neurologist at the Swiss Federal Institute of Lausanne, has triggered in patients by directly stimulating their brains with an electrode), the conscious subject of experience (what I consider “me”) is located in the double. That is, in an OBE, there are typically two representations: the visual one (you see your body lying on a bed, or on an operating table); and the felt one, where you feel yourself hovering above your “body.” This latter hovering you is the “double,” and it is here that the phenomenal self model (“me,” or my “ego”) seems to be located.  Hence the term, “out of the body:” “I” am out of my body.

            What this means, first and most importantly, is that being conscious means literally creating models—both of what is “out there,” and what is “in here.” We have brain-generated images of what the world “is” and what we “are”, and they work quite well in most cases; but they are not “real” in the sense we think they are—i.e. that “we” are in direct contact with what “is”. They are “virtual,” models that create a center for us, a center we experience as ourselves, as our first person perspective, and which we use to great advantage to do everything needed to survive. And the second and related meaning is that these models can and have been manipulated in scientific experiments, thus revealing their reality as models. That is, if we had a true and enduring picture of ourselves, we would not be fooled by rubber hands, phantom limbs, or OBEs. If we had a true and enduring picture of the world, we would not think that an evening sky is apricot-pink. As Metzinger notes, “there are no colors out there in front of your eyes. The apricot-pink of the setting sun is not a property of the evening sky; it is a property of the internal model of the evening sky, a model created by your brain. The evening sky is colorless. The world is not inhabited by colored objects at all…out there, in front of your eyes, there is just an ocean of electro-magnetic radiation, a wild and raging mixture of different wavelengths….What is really happening is that the visual system in your brain is drilling a tunnel through this inconceivably rich physical environment and in the process is painting the tunnel walls in various shades of color…For your conscious eyes only.”  Neuroscientists have evidence of this because of a type of brain injury called “apperceptive agnosia.”  This injury prevents the brain from forming a coherent visual model of the outside world, even though the patient’s visual apparatus is intact. So though they can “see,” patients with this injury cannot recognize what it is they are looking at. Their modeling equipment is disabled.

            I don’t know about you, but this gives me a kind of vertigo.

            So do statements like: “No such things as selves exist in the world.”

            Now the Buddha said this, over and over. Indian philosophy and religion talk about this and the related idea that what we take to be “real” is a dream, an illusion. But unless one experiences this “selfless” state for long periods of time, or consistently, this is something most people take on faith, if at all. But now, neuroscientists can refer to something like Cotard’s syndrome, a kind of selfless experience caused by brain malfunction. In it, patients stop using the first-person pronoun and, actually claim that they do not really exist. Metzinger mentions one patient who described herself as “Madame Zero.” The idea seems to be that, again, some part of the self-modeling apparatus is disabled. Metzinger follows this with another key idea: in order to have the feeling of “being someone,” you have to feel that you “own” your body, its sensations, and so on. And this too, is malleable: sports figures like skiers, race car drivers, and others often relate the sensation that their consciously sensed “body” at times is extended to include their skis, the cars they drive, and so on.

            What, then, is the essence of selfhood? Again, ownership seems to be the minimal condition (Metzinger demonstrates that neither a “seeing self”, emotions, will or thoughts are necessary—shut your eyes and your sense of self remains.) His theory then becomes something like this:

            Minimal self-consciousness is not control, but what makes control possible. It includes an image of the body in time and space (location) plus the fact that the organism creating this image does not recognize it as an image (because of the ‘tunnel’). But the important part is that “we discover that we can control the focus of attention. That we can actively control what information appears in our mind.” And then, taking off from experiments demonstrating that monkeys can control robots (called “slave” robots) by means of their thoughts, Metzinger hits us with this zinger:

            “The conscious experience of being a subject arises when a single organism learns to enslave itself.” That is, when it feels as if “I” control myself, or my body-slave.

            There are insights and mind-bending statements like this in every part, almost every page of Metzinger’s book and they are too numerous to recount. I will end this discussion, therefore, with Metzinger’s reflections on the notion of “free will.” To begin with, much prior brain research has already established the fact that subpersonal brain events (those that specify action goals and assemble motor commands) arise and begin actions before you are conscious of having the idea to “do” something. But since they do at some point become “conscious,” and thus become bound into the self-model active in your brain, you “experience them as your own thoughts, decisions, or urges to act—as properties that belong to you, the person as a whole.” Thus, it feels as if we are able to simply think about doing something, and then have our bodies make it happen. “We” control our bodies. Metzinger describes this as “the appearance of an agent”—i.e. someone who makes something happen, someone who is in control of his own actions. And free will depends intimately on this idea of “agency.” We feel we are able to do what we want to do, or rather, that what we do is done because we, our conscious selves, our PSM, want to. Moreover, this freely willing self-model is not a production of our minds alone; it involves the social life we engage in around us. Free will is like that: it is a social institution. Metzinger then discusses the implications of the fact that free will, or agency, is only an appearance in our model of ourselves:

            The assumption that something like free agency exists, and the fact that we treat one another as autonomous agents, are concepts fundamental to our legal system and the rules governing our societies—rules built on the notions of responsibility, accountability, and guilt. These rules are mirrored in the deep structure of our PSM, and this incessant mirroring of rules, this projection of higher-order assumptions about ourselves, created complex social networks. If one day we must tell an entirely different story about what human will is or is not, this will affect our societies in an unprecedented way. For instance, if accountability and responsibility do not exist, it is meaningless to punish people (as opposed to rehabilitating them) for something they ultimately could not have avoided doing. (p. 128)

Think about this. Virtually every religion and ethical/legal system known to humanity depends on the idea that people are responsible for their actions, and therefore must be held responsible.  “You committed murder. You knew what you were doing, you thought it up and wanted to do it, and decided to do it knowing the consequences, and therefore you must pay.” But what brain research seems to be showing us is that, though we cannot really comprehend it ourselves, most of what we do is already decided by our body/brains before our “conscious selves” or models think about it, and “decide” to do it, and rationalize it. Indeed, that these “conscious selves” are models that are useful illusions, but not really free agents in the strict sense of the word. What then?

            This is only one of the mind-bending conundrums raised by this book. For anyone who finds this type of deep contemplation fascinating, I recommend that you search out Metzinger’s book, read it, cogitate on it. I think I can safely say you’ll never be quite the same.


Lawrence DiStasi

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