Human Intracranial Electrophysiology

This study will enroll patients with epilepsy who are being evaluated for epilepsy surgery and have electrodes implanted in the brain and/or have electrodes on the scalp. Additionally, this study will recruit normal and online controls (participants who do not have epilepsy). Participants will be asked to participate in 1 to 2 (30-90 minutes) daily sessions designed to test aspects of human cognition such as memory, speech, language, feeling, movement, attention, sound perception, and emotions. Generally, this will involve working on a computer, looking at pictures or watching videos, and answering questions. Additionally, participants may be asked to be hooked up to additional equipment such as eye tracker, electrical stimulator, heart rate monitor, sweat monitor or other non-invasive equipment. The overall aim of this study is to use human intracranial electrophysiology (the recording of the electrical activity of the human brain) to study localization and function of the human brain.

This project aims to study the mechanisms of brain function by using Human Intracranial Electrophysiology (HIE) methods and is a continuation of the "Localization of Human Brain Function" study done at Dartmouth-Hitchcock Medical Center (DHMC). HIE refers to the recording of brain signals using electrodes which are surgically inserted into the human brain for the clinical purpose of localizing the origins of epileptic seizures.

Secondary to clinical goals, such patients with intracranial EEG electrodes can be safely recruited to participate in research studies, i.e. the research "piggybacks" on procedures that are performed strictly for a clinical purpose. Brain signals obtained using HIE methods during performance of specific tasks have unique properties rich with insight into the inner workings of the human brain. HIE methods can be used together with electrical brain stimulation (EBS) techniques to better understand relationship between brain and behavior. Furthermore, HIE methods can be recorded together with other non-invasive bio-physiological data streams such as pupillometry, electrodermal activity (EDA), cardiac monitoring, and respiratory monitoring to understand the relationship between the brain and many aspects of human physiology.

Eligibility Criteria:
Patients with Intracranial EEG: Inclusion Criteria

* Patients must be age 18 years or older. There is no upper age limit.
* Patients must have a diagnosis of refractory epilepsy undergoing intracranial EEG recording for clinical purposes.

Patients with Intracranial EEG: Exclusion Criteria

* Patient has additional neurological condition (such as stroke or dementia) or a psychiatric condition (such as active psychosis or suicidal ideation) and are deemed inappropriate for the study
* Patients are not able to provide informed consent for any reason (e.g. encephalopathic, experiencing a seizure)

Patients with Scalp EEG: Inclusion Criteria

* Patients must be age 18 years or older. There is no upper age limit.
* Patients must have a probable diagnosis of epilepsy.

Patients with Scalp EEG: Exclusion Criteria

* Patient has additional neurological condition (such as stroke or dementia) or a psychiatric condition (such as active psychosis or suicidal ideation) and are deemed inappropriate for the study
* Patients are not able to provide informed consent for any reason (e.g. encephalopathic, experiencing a seizure)

Normal Controls: Inclusion Criteria

* Participants must be age 18 years or older. There is no upper age limit.
* Participants must be able to provide informed consent for themselves.

Normal Controls: Exclusion Criteria

• Determined not to be appropriate normal control for the study population