Other researchers have achieved similar results using devices that capture brain waves through electrodes on the scalp. But some scientists think implanted devices hold the greatest promise because they pick up signals directly from the region of the brain responsible for movement.
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A wire the thickness of a strand of vermicelli carried the impulses from the brain to a half-inch-tall pedestal attached to the skull. From there, an external cable transmitted the signals to a computer.

Nagle played games such as Pong and Tetris, and while his reflexes were not quite on the same level as a gamer using traditional controls, he was able to defeat various lab technicians in Tetris, and achieved a mastery of the mental method after four days of practice. (Thanks romulan!)