Human Intracranial Electrophysiology

Not Applicable

Recruiting

• Conditions: Epilepsy

• Registration Number: NCT05529264
• Lead Sponsor: Dartmouth-Hitchcock Medical Center

Brief Summary

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.

Detailed Description

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.

Study Timeline

• Study First Submitted: 2022-08-22
• Study First Submitted QC: 2022-09-01
• Study First Posted: 2022-09-07
• Study Start: 2023-01-17
• Status Verified: 2023-07
• Last Update Submitted: 2023-07-11
• Last Update Posted: 2023-07-12
• Primary Completion: 2027-08-01
• Study Completion: 2032-08-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 175

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Using scalp and intracranial EEG, measure changes in electrical activity of the human brain associated with memory.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Primary objective is to use human intracranial electrophysiology to study localization and function of the human brain. With continuous recording of the electrical activity in participants' brain, study participants will be asked to take part in research tasks involving memory. The researchers will use the information to further the understanding of the exact location of cognitive functions.
Using scalp and intracranial EEG, measure changes in electrical activity of the human brain associated with emotions.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Primary objective is to use human intracranial electrophysiology to study localization and function of the human brain. With continuous recording of the electrical activity in participants' brain, study participants will be asked to take part in research tasks involving emotions. The researchers will use the information to further the understanding of the exact location of cognitive functions.
Using scalp and intracranial EEG, measure changes in electrical activity of the human brain associated with attention and executive function.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Primary objective is to use human intracranial electrophysiology to study localization and function of the human brain. With continuous recording of the electrical activity in participants' brain, study participants will be asked to take part in research tasks involving attention and executive function. The researchers will use the information to further the understanding of the exact location of cognitive functions.
Using scalp and intracranial EEG, measure changes in electrical activity of the human brain associated with movement.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Primary objective is to use human intracranial electrophysiology to study localization and function of the human brain. With continuous recording of the electrical activity in participants' brain, study participants will be asked to take part in research tasks involving movement. The researchers will use the information to further the understanding of the exact location of cognitive functions.
Using scalp and intracranial EEG, measure changes in electrical activity of the human brain associated with language.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Primary objective is to use human intracranial electrophysiology to study localization and function of the human brain. With continuous recording of the electrical activity in participants' brain, study participants will be asked to take part in research tasks involving language. The researchers will use the information to further the understanding of the exact location of cognitive functions.
Using scalp and intracranial EEG, measure changes in electrical activity of the human brain associated with sound perception.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Primary objective is to use human intracranial electrophysiology to study localization and function of the human brain. With continuous recording of the electrical activity in participants' brain, study participants will be asked to take part in research tasks involving sound perception. The researchers will use the information to further the understanding of the exact location of cognitive functions.

Secondary Outcome Measures

Name	Time	Method
The degree of correlation between the brain activation and respiratory activity.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Researchers will investigate the degree of correlation (correlation coefficient or how similar the measurements are) between the human intracranial EEG signals and respiratory activity. The respiratory activity (e.g. breathing rate, oxygen level, etc.) will be measured with non-invasive sensors such as respiratory belt worn around a participant's chest and abdomen as well as a small sensor under their nose.
Measure the degree of correlation between the brain activation and sweat variations.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Researchers will investigate the degree of correlation between the human intracranial EEG signals and sweat volume. The researchers will use use a Q-SWEAT system to noninvasively measure the sweat volume produced during specific study tasks. The Q-SWEAT system has a multicompartmental capsule, which is placed tightly on the skin, often in four standard locations (the dorsal foot, distal leg, proximal leg, and forearm), though any flat, area of skin can be used. Nitrogen gas flows through the inner compartment, and the system detects sweat volume by measuring changes in the relative humidity of returning nitrogen during the recording period.
Measure the degree of correlation between the brain activation and cardiac physiology.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Researchers will use a CNAP machine (finger sensor) to record heart-rate variability. The CNAP machine will measure the waveform and pressure continuously, which will allow for detection of changes in blood pressure without using an arterial line or other invasive methods. Researchers will investigate the degree of correlation between the human intracranial EEG signals and heart-rate variability, including changes in blood pressure during the performance of study tasks.
The degree of correlation between the brain activation and electrodermal activity.	Evaluated for each patient during monitoring period of approximately 2 weeks.	Researchers will investigate the degree of correlation between the human intracranial EEG signals and electrodermal activity (electrical characteristics of human skin). The electrodermal activity will be measured with non-invasive electrodermal sensors such as wrist or ankle sensors and expressed as a variation in electrical characteristics of participants' skin.

Trial Locations

Locations (1)

Dartmouth-Hitchcock Medical Center; 🇺🇸 Lebanon, New Hampshire, United States