We will observe epileptic patients who already have electrodes implanted on the brain and are receiving high-level brain stimulation for clinical purposes while testing their motor and language function. We propose to do a limited, low-level brain stimulation to show that the signatures of local activity in the target area change as an effect of brain stimulation. The goal of this study is to understand the feasibility of a novel recurrent brain-computer interface that could eventually promote targeted functional recovery in subjects who have had a brain injury.

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.

Inclusion Criteria:

• Age 18 and older
• Male and Female
• Able to understand English for consenting and testing
• Referred for surgical implantation of electrodes

Exclusion Criteria:

• Under 18 years of age
• Pregnant women
• Prisoners
• Mentally disabled IQ < 70
• Non English Speaking
• Not candidates for surgical implantation of electrodes

Age 18 and older male and female epileptic patients who are referred for surgical implantation of electrodes.