kkleiner writes "A group of 15 patients suffering from either epileptic seizures or brain tumors volunteered to allow scientists to insert electrodes into their brains. After neurosurgeons cut a hole in their skulls, the research team placed 256 electrodes over the part of the brain that processes auditory signals called the temporal lobe. The scientists then played words, one at a time, to the patients while recording brain activity in the temporal lobe. A computer was able to reconstruct the original word 80 to 90 percent of the time."
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