Sensors shown underneath a skull
Electrocorticography (ECoG), placing sensors underneath the skull, directly on the brain. Data is taken intrusively right from the brain's surface. Several people have already undergone the implantation of sensors for the study of Epileptic Seizures. A recent patient move the "Space Invaders" gun in 1 dimensional plane effectively.
Now researchers are seeing in this same technology can be used to control a cursor on a computer screen. A group of 4 patients were asked to think of sounds, phonemes, "oo", "ah", "ee" and "eh." The brain-waves were recorded for those thoughts. Patients were asked to think of those sounds to move a cursor in the 4 directions it could go. Results shown that the cursor placement was accurate and repeatable.
Lead researcher on the project, Eric Leuthardt, states that a large mesh of sensors is not needed for machine interfacing with the brain. A 4mm x 4mm sensor would suffice. Research continues at the Washington University in St. Louis.
Eavesdropper