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But you did seem to be attempting to tar the whole of cog-sci with some sort of Cartesian brush, so it's useful to know that isn't your intention. Quote:
With reference to Müller-Lyer, there's no doubt at all that something in the brain codes the lines as being of different lengths: lines of the same length are projected on the retina, and the words "These lines are different lengths" come out of the mouth. Between those two events lies nothing but brain activity (if you'll allow me to include retinal processing under the umbrella of the brain). So saying that somewhere in the brain the lengths of the lines are perceptually altered is a truism, unless you believe that there really is a "liar" in Müller-Lyer. Quote:
So from where I stand you seem to be tilting at non-existent windmills. Grant Hutchison |
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The anterior part of the frontal lobes does appear to be involved in "personality", in the sense of controlling the range of emotions individuals characteristically exhibit: a pattern that becomes recognizable to others and which is one feature of "personality". Hence the unfortunate vogue for Walter Freeman's prefrontal lobotomies, applied to people with various behavioural problems in the 40s and 50s. The most famous prefrontal lobotomy patient in the world is probably Phineas Gage, who underwent the procedure under uncontrolled circumstances. While he was working as a railway construction foreman, an explosion sent a tamping iron straight through his head: there's a diagram of the extent and nature of of his injury here. He recovered consciousness almost immediately, and lived for another 12 years, but his personality had changed completely. Although this is often quoted as an example of the prefrontal cortex's role in the generation of personality, I've always felt there was a significant confounding factor involved: the guy had had a metal rod blown through his face and out the top of his head, for crying out loud! That might just change your outlook on life, all on its own. Grant Hutchison |
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I don't know if this applies as a pre-frontal cortex sitution or not, but my father's personality dramatically shifted in his thirties, along with some physical symptoms, like blackouts, that were later attributed to a benign cyst on the exterior right hand side of his head just aft of the cheek. The doctors postulated that it was pressure from this on a part of his brain in that region that drove him to hair trigger temper and near psychotic violence. After it was removed, his personality 180'd. Completely controlled and cool. It was definitely not very deep inside the brain, in fact, based on the descriptions I've heard, I believe it was on the surface. Now, it could have been a chemical issue, but that would indicate the potential to alter personality through pressure somewhere other than the interior of the brain.
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I'm not completely heartless, the doctor who removed it told me he'd never be able to get it all. |
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António Damásio talks about Phineas' case and other intriguing ones in Descartes' Error.
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"All your bias are belong to us." Ara Pacis "A witty saying proves nothing." Voltaire |
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The common, traditional (representational) view of vision may go something like this: Although I think I see objects around me, all I really know for sure is that I am having a conscious experience of there being objects. Science tells us that the world is really a colorless cloud of atoms, but I see the world in vivid color. Consciousness, then, must be a creation of my brain. It creates these phenomena, qualia, appearances, or representations as philosophers call them. Because I perceive only representations, any reality or noumemon that may ultimately be behind them must necessarily remain unknown. Experiences we take as visual failure like misreading a word, optical illusions, and so on are explained by the brain creating the wrong representation or creating a representation that fools us. Non-representational approaches don't consider perception as a thing, and certainly not a thing created or assembled by the brain. Remember one of the earlier quotes: Perception is an achievement of the individual and not an experience the theater of consciousness. Take a look at the abstract on the first page: A Sensorimotor Account of Vision and Visual Consciousness (PDF) In the 1960's, psychologist JJ Gibson proposed studying perception from an ecological viewpoint. He suggested studying visual perception in terms of the ambient optic array, that is, the patterned radiation that converges on your position as well as how it changes as you move about (optical texture flow). He thought that most if not all of what we think is created in the head actually exists in the environment as higher-order information that animals can detect and take advantage of. Here is an excerpt from his book. You can glance at the pictures and the captions to get a sense of his interests: The Causes of Deficient Perception Quote:
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I think there is a justified fear of attributing the act of composition to a mere machine (which the body may seem to us at times). Gilbert Ryle showed the premise to be misguided. He wrote in The Concept of Mind: "Man need not be degraded to a machine by being denied to be a ghost in a machine. He might, after all, be a sort of animal, namely, a higher mammal. There has yet to be ventured the hazardous leap to the hypothesis that perhaps he is a man." Quote:
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The phrase "perception is an achievement of the individual" is neatly analogous to the guilty child's explanation of the broken mirror: "It just broke." Grant Hutchison |
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As for pain, there wasn't that, just pressure on the brain itself. He had absolutely no localized awareness anything was going on upstairs. The brain itself is insensate, so I've read.
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I'm not completely heartless, the doctor who removed it told me he'd never be able to get it all. |
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Edited to add: By the way, Ken, Grant's response, which is a fair one from the representational side, is what I had in mind with the "Hey, where are the vortexes?" Newton-era analogy. The representational side will always think that there is a hard problem of consciousness that non-representationalists are skirting. |
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Grant Hutchison |
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laws of sensorimotor contingency." In other words, seeing is as seeing does. A classic example of what I have called "a projection". It is perfectly obvious to me that this projection may reveal interesting things about vision, just as it is equally obvious that it will leave out important pieces of the puzzle. It's the perfect example of the kind of logic I've been objecting to-- arguing that since a shadow is a good way to understand a person's outline, the color of their shirt must be a delusion of some kind. Quote:
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If we understood everything going on in the head of a pin... we still wouldn't know not to step on the pointy end. People think the problem with models is that they are limited by our minds, but the greater problem is that our minds are limited by our models. |
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It surprises me to hear you say that, because as I understand the term, you would be "coming from the representational side" any time you ask someone "does this hurt", instead of waiting for them to moan or kick or interact with the environment in some way. I'm not saying that you need to adopt a philosophical stance on consciousness each time you ask that question, merely you pop on a hat because of its immediate advantages. Indeed, the whole idea of adopting a general philosophical stance is what I'm criticizing, and perhaps that's what you mean when you say you are not "coming from" any particular philosophical stance, be it representational or otherwise. Also, psychotherapy almost always treats the patient's mind as if it were a separate entity from whatever is going on around it-- the techniques of psychotherapy are intended to work in a wide array of environmental situations, without the therapist actually encountering that environment at all, and seems pretty "representational" to me.
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If we understood everything going on in the head of a pin... we still wouldn't know not to step on the pointy end. People think the problem with models is that they are limited by our minds, but the greater problem is that our minds are limited by our models. |