The more time scientists spend designing computers, the more they marvel at the human brain. Tasks that stump the most advanced supercomputer—
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a face, reading a handwritten note are child"s play for the 3-Ib.
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. Most important, unlike any conventional computer, the brain can learn
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its mistakes. Researchers have tried for years to program computers to
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the brain"s abilities, but without success. Now a growing number of designers believe they have the answer: if a computer is to
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more like a person and less like an over-grown calculator, it must be built more like a brain, which distributes information across a vast interconnected web of
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cells, or neurons.
Conventional computers function by following a chainlike sequence of detailed
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. Although very fast, their processors can perform only
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task at a time. This approach works best in solving problems that can be broken down into simpler logical pieces. The processors in a neural-network computer, by contrast,
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a grid much like the nerve cells in the brain. Since these
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neurons are interconnected, they can share information and perform tasks at the same time. This two-dimensional approach works best at recognizing patterns.
Instead of
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a neural-network computer to make decisions, its makers trains it to recognize the patterns in any solution to a problem
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repeatedly feeding examples to the machine.
Neural-network computers come in all shapes and sizes.
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now most existed as software simulations because redesigning computer chips
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a lot of time and money. By experimenting with different approaches through
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rather than hardware, scientists have been able to avoid costly mistakes.