Word: mentalities
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Dates: during 1990-1999
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...their passage reinforces the particular set of connections between this particular set of neurons, giving them the ability to re-create the image. The more often the pattern is reinforced-by repeated sightings of the person, by the effort to remember him or by connection with some other mental trigger ("This woman is attractive; she's worth getting to know better," or, "This man looks unpleasant; I need to avoid him")-the more likely, says Damasio, the pattern, or image, will not go into short-term memory, lasting weeks or months, but into permanent, long-term memory. And from there...
...brain's need to fill in the blanks is the phenomenon of phantom limbs. When an arm or a leg is amputated, the victim almost invariably "feels" sensations like pain or itching, often very strongly, in the missing limb. What's happening? The brain carries within it a mental map of the body, a well-formed sense of where every part is in relation to every other. That's why it's possible for you to extend your arm and then, with your eyes closed, bring it in to touch the tip of your nose. (Drunkenness distorts your perception...
Even when a limb is gone, its place on the mental map remains, and the neurons formerly responsible for processing sensations from it occasionally fire at random-the sensory equivalent of Mickey Mouse hallucinations. The brain also attempts to make up for the deficit physically, perhaps, suggests Ramachandran, by sprouting new sets of connections. Because neurons that process information from the arm are near those that handle the face, for example, these new connections can cause a blindfolded patient to think a gentle touch on the face is really a touch on a missing fingertip. Says Ramachandran: "Reorganization can occur...
...category "horse" but cannot supply the example "Appaloosa." He knows "U.S. President" but not Harry Truman or Richard Nixon. Somewhere in his brain, the data may still exist, but he can no longer get at them. The reason, argue the Damasios, is that he has lost essential "convergence zones," mental switching stations that provide access to the information and relate it to other relevant data...
These oscillations, Llinas believes, are the basic building blocks of consciousness. What the brain does, whether asleep or awake, he notes, is make images. But these are purely mental constructions, even when they're based on external information. For example, says Llinas, "light is nothing but electromagnetic radiation. Colors clearly don't exist outside our brains, nor does sound. Is there a sound if a tree drops in the forest and no one hears it? No. Sound is the relationship between external vibrations and the brain. If there is no brain, there can be no sound...