Scientists from the University of Utah have found a way to let paralyzed people communicate through the use of microelectrode implants on top of the brain:
Brain signals of paralyzed people can be translated into words through the use of two grids of 16 microelectrodes which are implanted above the brain and beneath the skull. But unlike many other types of electrodes, these microelectrode implants are much smaller than traditional electrodes developed half a century ago and they don't penetrate the brain at all -- they simply sit on top of it. These microelectrodes are called microECoGs, and their ability to work without penetrating the brain makes them safer for speech areas of the brain, which cannot be said for penetrating electrodes up to this point.
The microelectrode implants work by placing the microECoGs, each spaced 1 millimeter apart, on two different speech areas of the brain: the facial motor cortex and the Wernicke's area. The facial motor complex controls movement of the lips, mouth, tongue and face while Wernicke's area is a "little understood" area in the brain that is linked to language understanding and comprehension.