The goal of this project is to study how the brain reacts to a small electrical signal. Researchers will be using a novel combination of recording electrodes. The researchers will measure the brain response from these electrodes.

Inclusion Criteria:

• Patients with medication intractable epilepsy who are recommended to undergo brain surgery to remove a "seizure" focus
• Can provide informed consent for the study and willing to participate

Exclusion Criteria:

• Presence of a permanent electronic implant
• Any chronic medical conditions that prevent safe placement of electrodes

The aspects of a plan for sharing are still under determination.