The subject will have already been scheduled for placement of the ECoG electrodes on the surface of the brain and who will, for all clinical purposes, subsequently receive stimulation for mapping of function of the ECoG sites. The decision to place the electrodes on the brain, the location of the electrodes and the length of time the electrodes are in are all part of clinical care.
There will be two types of testing, motor and language. Motor will involve inducing stimulation to the thumb cortex and the wrist cortex. There will be a conditioning of this over 4-12 hours. Language will involve showing pictures on a computer screen and the subject will be observed whether speech is disrupted with stimulation or not.