Hippocampal Oscillations During Exploration

Not Applicable

Not yet recruiting

• Conditions: Epilepsy

• Registration Number: NCT07224191
• Lead Sponsor: NYU Langone Health

Brief Summary

The objective of this study is to determine how visuomotor exploration relates to hippocampal activity along its long axis. The study will investigate the neurophysiological mechanisms in the hippocampus during (1) visual exploration in surgical patients using high-resolution iEEG, and (2) ambulatory exploration in patients implanted with RNS devices.

Detailed Description

Aim 1 - Visual Exploration in Surgical Patients Investigators will study 20 surgical patients with high-resolution intracranial EEG (iEEG) to investigate hippocampal activity during visual exploration. Participants will view between 10-15 panoramic environments using Meta Quest AR/VR glasses while their eye movements and head turns are tracked. Eye-tracking, head-turn, and iEEG data will be synchronized with visual stimuli, and intracranial EEG and single-unit data will be analyzed for changes in neuronal firing and brain activity before and after saccades.

Aim 2 - Ambulatory Exploration in RNS Patients and Healthy Controls Investigators will study 12 epilepsy patients with implanted responsive neurostimulator (RNS) devices and 24 healthy controls (HCs) during real-world exploration. Participants will walk through and explore visually distinct rooms while wearing synchronized high-density EEG (hdEEG), eye-tracking glasses, and body position sensors. Data from hippocampal iEEG, hdEEG, eye tracking, and motion sensors will be synchronized offline to examine brain-behavior relationships and the influence of cognitive load on saccade-hippocampal interactions.

Study Timeline

• Status Verified: 2025-10
• Study First Submitted: 2025-10-31
• Study First Submitted QC: 2025-10-31
• Last Update Submitted: 2025-10-31
• Study Start: 2025-11-01
• Study First Posted: 2025-11-04
• Last Update Posted: 2025-11-04
• Primary Completion: 2028-10-08
• Study Completion: 2028-10-08

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 56

Inclusion Criteria

All subjects:

• Adults (18-70 years)
• Able to provide informed consent

Aim 1: Surgical epilepsy patients' inclusion criteria

• Implanted hippocampal depth electrodes for Stage 1 epilepsy surgery
• IQ=>80*

Aim 2: RNS patients Inclusion criteria

• Implanted RNS device with at least one hippocampal depth electrode
• At least 5 months post-implantation to avoid the post-implant effect
• Have a relatively low number of seizures, defined as =<1 debilitating seizure per week
• Able to walk and wear research equipment without assistance
• IQ>=80

Aim 2: Healthy Control Inclusion criteria • Able to walk and wear research equipment without assistance

Exclusion Criteria

RNS patients, Aim 2:

• Any generalized tonic-clonic seizure(s) within the last year

All subjects:

• Legally blind
• Smoking tobacco, marijuana, recreational drugs or alcohol use within 1 week of cognitive testing
• Unable to give informed consent
• Pregnancy

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Hippocampal Theta Power Under High Cognitive Loads	Study Visit (Day 1)	Aims 1 and 2. High cognitive loads defined as visual exploration of a complex scene with goal-driven task.
Hippocampal Theta Power Under Medium Cognitive Loads	Study Visit (Day 1)	Aims 1 and 2. Medium cognitive loads defined as visual exploration of a simpler scene with fewer objects.
Hippocampal Theta Power Under Low Cognitive Loads	Study Visit (Day 1)	Aims 1 and 2. Low cognitive loads defined as visual exploration of moving dots.
Hippocampal Theta Power Under No Cognitive Loads	Study Visit (Day 1)	Aims 1 and 2. Low cognitive loads defined as staring at a blank field of view or REM sleep.
Coherence Time-Locked to the Saccade Under High Cognitive Loads	Study Visit (Day 1)	Aims 1 and 2. High cognitive loads defined as visual exploration of a complex scene with goal-driven task.
Coherence Time-Locked to the Saccade Under Medium Cognitive Loads	Study Visit (Day 1)	Aims 1 and 2. Medium cognitive loads defined as visual exploration of a simpler scene with fewer objects.
Coherence Time-Locked to the Saccade Under Low Cognitive Loads	Study Visit (Day 1)	Aims 1 and 2. Low cognitive loads defined as staring at a blank field of view or REM sleep.
Coherence Time-Locked to the Saccade Under No Cognitive Loads	Study Visit (Day 1)	Aims 1 and 2. Low cognitive loads defined as staring at a blank field of view or REM sleep.

Trial Locations

Locations (1)

NYU Langone Health; 🇺🇸 New York, New York, United States