Using neural activity recorded from a sheet of electrodes laid directly on the surface of a patient's brain, scientists can predict the movement of fingers, as well as which of several sounds the patient is imagining.

Eventually, researchers hope to use the findings to develop intuitive neural prostheses, such as a robotic hand that moves its fingers with as little mental effort as it takes to move real ones, or a computer interface that detects imagined words.

To realize this vision, scientists are also developing smaller, more flexible technology, which could be more easily implanted and make better contact with the brain.

Details of the latest brain-computer interface technology were presented this week at the Society for Neurosciences conference in Washington, DC.

Schalk and others are studying ECoG as a possible alternative to electrodes implanted into brain tissue.