All in the mind [Control Thought/Mind]

This article discusses brain-computer interfaces that are designed initially to help people who have lost control of their limbs but whose neurons responsible for these motor functions are still active, the system includes a silicon-array sensor a few millimetres square containing about 100 electrodes implanted in the brain´s motor cortex. The electrodes are wired to a pedestal mounted through the skull, and the pedestal is connected by a cable to a computer.This research falls across the three principal methods of measuring brain activity - noninvasive BCI, using electrodes placed separately on the scalp; partially invasive, via an electrode grid that sits inside the skull but on the surface of the brain; and invasive, where the grid is implanted into the grey matter itself.