Hippocampal Oscillations During Exploration

NYU Langone Health

Status: Not yet enrolling

Conditions: Epilepsy

Treatments: Other: Visual Exploration; Other: Ambulatory Exploration

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT07224191

R61DC022830-01 (U.S. NIH Grant/Contract)

25-01119

Details and patient eligibility

About

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.

Full 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.

Enrollment: 56 estimated patients

Sex: All

Ages: 18 to 70 years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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56 participants in 3 patient groups

Epilepsy Surgery Patients

Experimental group

Description:

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.

Treatment:

Other: Visual Exploration

Patients with RNS Devices

Experimental group

Description:

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).

Treatment:

Other: Ambulatory Exploration

Healthy Control Participants

Experimental group

Description:

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).

Treatment:

Other: Ambulatory Exploration