Researchers have made tremendous strides in developing ways for patients to move a computer cursor or even an artificial arm using electrodes implanted in the brain. But researchers have been reluctant to implant electrodes in the speech centers for fear of causing irreversible damage.
Some researchers have been attempting to "read" speech centers in the brain using electrodes placed on the scalp. But such electrodes "are so far away from the electrical activity that it gets blurred out," Greger said.
He and his colleagues instead use arrays of tiny microelectrodes that are placed in contact with the brain, but not implanted. In the current study, they used two arrays, each with 16 microelectrodes."
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