Hippocampal Oscillations During Exploration

Human Hippocampal Oscillations During Visuomotor Exploration

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.

Study Overview

• Status: Recruiting
• Conditions: Epilepsy
• Intervention / Treatment: Other: Visual Exploration; Other: Ambulatory Exploration

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 Type: Interventional
• Enrollment (Estimated): 56
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Anli Liu, MD, MA; Phone Number: (929) 455-2323; Email: Anli.Liu@nyulangone.org
• Study Contact Backup: Name: Ayelet Rosenberg; Phone Number: (646) 558-0893; Email: Ayelet.rosenberg@nyulangone.org

Study Locations

• United States
  • New York
    • New York, New York, United States, 10016
      • Recruiting
      • NYU Langone Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Epilepsy Surgery Patients; Aim 1: Participants will be presented with between 10-15 unique immersive virtual environments (depending on patient tolerance) for patients to explore using VR glasses. Control tasks will be run to account for eye movements during non-navigation. For recording eye movements in darkness during REM sleep, as part of a control task, 4 electrodes will be placed above and below both eyes, a standard technique in polysomnographic studies.	Other: Visual Exploration; Cognitive testing while admitted to the epilepsy monitoring unit (number of sessions will vary depending on patient availability and stamina).
Experimental: Patients with RNS Devices; Aim 2: Participants will walk between 4-6 rooms within an office floor. Each office will contain generic objects (office furniture, computers, lighting) and unique objects (artwork, photographs, books, and personal items). As control conditions, subjects will first be asked to walk around and between two empty rooms under different lighting conditions and speeds. Participants will also be asked to participate in all awake saccade control conditions (without a visual cognitive load).	Other: Ambulatory Exploration; Series of cognitive tasks completed during a study visit.
Experimental: Healthy Control Participants; Aim 2: Participants will walk between 4-6 rooms within an office floor. Each office will contain generic objects (office furniture, computers, lighting) and unique objects (artwork, photographs, books, and personal items). As control conditions, subjects will first be asked to walk around and between two empty rooms under different lighting conditions and speeds. Participants will also be asked to participate in all awake saccade control conditions (without a visual cognitive load).	Other: Ambulatory Exploration; Series of cognitive tasks completed during a study visit.

What is the study measuring?

Primary Outcome Measures

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

Collaborators and Investigators

• Sponsor: NYU Langone Health
• Collaborators: National Institute on Deafness and Other Communication Disorders (NIDCD)
• Investigators: Principal Investigator: Anli Liu, MD, MA, NYU Langone Health

Study record dates

Study Major Dates

• Study Start (Actual): February 25, 2026
• Primary Completion (Estimated): October 8, 2028
• Study Completion (Estimated): October 8, 2028

Study Registration Dates

• First Submitted: October 31, 2025
• First Submitted That Met QC Criteria: October 31, 2025
• First Posted (Actual): November 4, 2025

Study Record Updates

• Last Update Posted (Actual): February 27, 2026
• Last Update Submitted That Met QC Criteria: February 26, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epilepsy
• Other Study ID Numbers: 25-01119; R61DC022830-01 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The study will upload data into openneuro.org or comparable neuroscience data sharing platform, with data uploaded on a basis as specified by the conditions of awards supporting this research.
• IPD Sharing Time Frame: Beginning 9 months and ending 36 months following article publication or as required by a condition of awards and agreements supporting the research.
• IPD Sharing Access Criteria: Requests should be directed to anli.liu@nyulangone.org. To gain access, data requestors will need to sign a data access agreement. This instance of data sharing will also require separate IRB review as well as review from NYU Langone's DSSB.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes