The purpose of this study is to determine the feasibility of chronic ambulatory thalamus seizure detection. The sensitivity, specificity, and false alarm rate of thalamus seizure detection will be calculated using recordings from a deep brain stimulation system, assessed relative to concurrent gold-standard video-EEG monitoring collected in the in-patient setting (epilepsy monitoring unit), in 5 patients with drug resistant epilepsy.

Inclusion Criteria:

Participants must meet all of the inclusion criteria to participate in this study:

• 18 years of age and older.
• Implanted with a clinical DBS system for epilepsy with brain recording capabilities (Medtronic Percept™ DBS).
• Subject or legally authorized representative is able to understand study procedures and to comply with them for the entire length of the study.

Exclusion Criteria:

All candidates meeting any of the exclusion criteria at baseline will be excluded from study participation:

• Health status or any clinical conditions (e.g., life expectancy, co-existing disease) that, in the opinion of the site investigator, would pose undue risk to undergo epilepsy monitoring unit evaluation for the purpose of seizure characterization.
• Women will verify not pregnant, and if applicable, have urine pregnancy test.
• Current drug or alcohol use or dependence that, in the opinion of the site investigator, would interfere with adherence to study requirements.
• Inability or unwillingness of individual or legal guardian/representative to give written informed consent.