On Tue, Jun 7, 2011 at 5:53 AM, Pete Hughes <pet...@gmail.com> wrote:
> Jason, > > I found this compelling, are you saying that the difficulty of explaining > qualia is due to the language centre of the brain being able to access only > an abstract 'interface' (I'm a object oriented thinker) of the sensors? then > what about emotions? I'm trying to pre-empt your response to 'why don't you > put your hand in the fire and enjoy the information' and I just can't, I > like the way you talk so I will pester you with the question. > Peter, Thanks, I am happy to attempt an answer. The below is a conclusion from taking seriously http://en.wikipedia.org/wiki/Modularity_of_mind which is supported by several pieces of evidence: 1. Anesthesia The naive view is that anesthetics work by turning off the brain or causing activity in it to cease. This is incorrect, there is still a great deal of activity within an anestetized mind, yet consciousness is abolished. The person is unable to move, remember, sense pain, etc. Yet other brain functions, such as regulating blood pressure or heart rate continue. The leading theory for why this is, is called cognitive unbinding. Anesthetics operate by confusing or dampening communication between neurons. Cognitive unbinding proposes that this causes disparate brain regions to become cut off from each other as neural signals can only travel so far given the interference of the chemicals. The result is different brain regions are cut off from each other, the pain processing part of the brain doesn't receive information from the touch processing part of the brain, the hippocampus doesn't receive information to encode as memories, the muscles don't receive signals to move which are under conscious control, yet independent brain functions (which don't require interaction with other brain regions) such as those that control breathing or heart rate continue to function. It is not the sheer will to survive which keeps the lungs breathing or heart pumping, as animals which are conscious breathers (such as the dolhpins and whales) will suffocate under anesthesia. This also forbids them from sleeping, they rest only one hemisphere of their brain at a time. 2. Different forms of brain damage Visual information is a cast collection of processed information. Before the image reaches your conscious awareness your brain has applied edge detection, depth and color perception, object recognition, motion sensing, and blind spot extrapolation, among other things. Each of these functions independently and can be impaired or lost without affecting other parts of the brain. There are cases where brain damage to the V5 section of the brain causes motion blindness (sufferers see the world as a collection of static frames, devoid of any concept of motion), likewise people can lose the ability to recognize faces, or recognize objects (these functions occur in different parts of the brain, so while someone might lose the ability to recognize objects they can still recognize faces and vice versa), finally there are people who have lost the ability to process colors. Not only can they no longer see colors, but they lose the ability to recall colors altogether. Since the processing is done in specific areas of the brain, these modules share only the high-level results of their processing with other brain regions. (This is the limited-access part of modularity). It is not possible for all areas of the brain to do everything independently of course, so if they interact with other brain regions, they must receive high level results, not the raw input that a particular module processed. 3. Pain perception This is getting close to your question on emotions and why people don't stick their hand in the fire. It's been found that the perception of pain is handlered in one part of the brain, but what makes pain painful (unpleasent) is handled by an entirely different part of the brain: the anterior cingulate cortex. Damage to this part of the brain (or severing nerves connected to it in an operation called a cingulatomy) brings about the curious phenomenon of pain dissociation. Someone with pain dissociation can provide specific information about the location and intensity of the pain, but it no longer bothers them or causes any distress. An example: Paul Brand, a surgeon and author on the subject of pain recounted the case of a woman who had suffered with a severe and chronic pain for more than a decade: She agreed to a surgery that would separate the neural pathways between her frontal lobes and the rest of her brain. The surgery was a success. Brand visited the woman a year later, and inquired about her pain. She said, “Oh, yes, its still there. I just don't worry about it anymore.” With a smile she continued, “In fact, it's still agonizing. But I don't mind.” To answer your question about emotion I think Marvin Minsky provides a good answer. You might say that given the above description of pain perception, we have only defined that feelings in terms of its effect on how we think, you might object that I have only described how hurting affects the mind but we still can't express how hurting feels. Marvin Minsky called this: “a huge mistake-that attempt to reify 'feeling' as an independent entity, with an essence that's indescribable. As I see it, feelings are not strange alien things. It is precisely those cognitive changes themselves that constitute what 'hurting' is-and this also includes all those clumsy attempts to represent and summarize those changes. The big mistake comes from looking for some single, simple, 'essence' of hurting, rather than recognizing that this is the word we use for complex rearrangement of our disposition of resources.” According to Minsky, human consciousness involves the interplay between as many as 400 separate sub-organs of the brain. If you try to imagine the resulting symphony of activity that comes from these individual regions, each acting on each others' signals and in turn reacting to how those other regions are then affected, you can see it becomes a kind of perpetual and intertwined feedback loop of enormous complexity. I think in short, emotions represent changes to a large number of different brain regions simultaneously. Jason > > "Your brain contains information received by the senses, it is a system > which can enter many different states based on that information (it > interprets it). One of those states is your brain thinking about the fact > that it knows it is touching the back of your hand with one of your fingers > (that may represent only a few bits of information), now consider that your > brain has 100,000,000,000 neurons and you can begin to see that more complex > qualia such as vision involve vastly greater amounts of information (some > 30% of your cortex is devoted to processing visual information). Together > with the modularity of mind (different sections are specialized and compute > different things, and share the results with other brain regions), you can > begin to see why qualia such as Red or Green are so hard to explain. > Consider Google's self-driving cars. They need to determine whether the > stop light is Yellow, Red or Green. The cameras collect many MB worth of > raw R,G,B data per second which is processed by a specialized function which > determines the state of the stop light. The result Red, Green, or Yellow is > transmitted to other parts of the driving software, for example the parts > which control acceleration. This part of the software knows there is a > difference between "Light is Red" vs. "Light is Green", but it cannot say > how they are different or why it knows they are different (this was decided > elsewhere). It is much like the verbal section of your brain trying to > articulate the difference between red and green, it knows they are different > but cannot say how. It does now have access to the raw data received from > the millions of cones in your retina." > > > -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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