Brain Stimulation and Visually-guided Navigation

NCT ID: NCT04961645

Last Updated: 2025-04-24

Basic Information

• Recruitment Status: TERMINATED
• Clinical Phase: NA
• Total Enrollment: 11 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2023-03-03
• Study Completion Date: 2023-05-17

Brief Summary

This study investigates the neural mechanisms causally involved in how people navigate through their immediately visible environment (e.g., walking around one's bedroom flawlessly and effortlessly, not bumping into the walls or furniture). To investigate whether particular neural mechanisms are causally involved in "visually-guided navigation", repetitive transcranial magnetic stimulation (rTMS) is used to temporarily disrupt the functioning of particular brain regions in healthy adults while they are shown simple visual stimuli of places (e.g., bedrooms, kitchens, and living rooms) and asked to perform simple computer tasks or to complete simple behavioral tasks.

Detailed Description

Human ability to navigate through the immediately visible environment is crucial for survival. However, the representations and computations underlying this remarkable ability are not well understood, and current computer vision algorithms (robots) still lag far behind human performance. One promising strategy for attempting to understand "visually-guided navigation" is to characterize the neural systems that accomplish it. The results from functional magnetic resonance (fMRI) on adult humans have begun to elucidate the cortical regions involved in visually-guided navigation, with the central finding that there is at least one visual cortical region - called the occipital place area (OPA) that may play a central role in the ability to navigate through currently visible places (e.g., walking around our bedroom flawlessly and effortlessly, not bumping into the walls or furniture our bedroom). However, fMRI is a correlational method, and research still needs to determine if this functionally specific brain region is causally involved in visually-guided navigation. Understanding the causal involvement of this region will provide important clues about how humans navigate their world, and also perhaps someday be harnessed to help those individuals who devastatingly lose the ability to navigate, as a result of eye diseases, brain surgery, stroke, neurodegenerative diseases, or developmental disorders.

The use of rTMS to investigate the causal involvement of particular brain regions in particular human abilities is not novel, having been used to investigate face recognition, scene recognition, and object recognition. The general question for this research is to determine, using rTMS, the causal involvement of OPA in visually-guided navigation.

Participants will have an fMRI scan to identify the OPA location in each individual participant. Once the OPA location is known, participants will receive the rTMS study intervention.

Conditions

Healthy Participants

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: SEQUENTIAL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Repetitive Transcranial Magnetic Stimulation (rTMS) During Computer-based Task

Participants receiving rTMS while they perform computer-based tests to examine the causal involvement of OPA in visually-guided navigation. The study visit lasts approximately 90 minutes.

Group Type: EXPERIMENTAL

Repetitive Transcranial Magnetic Stimulation (rTMS)

Intervention Type: DEVICE

TMS is a safe and noninvasive method for affecting brain function relying on the properties of electromagnetic induction. Action potentials are triggered in neurons, along with a subsequent period of deactivation. Normal ongoing brain activity is disrupted providing a way for investigators to produce a transient and reversible period of brain disruption.

Computer-based Test

Intervention Type: BEHAVIORAL

Participants will be seated comfortably in a chair and asked to complete a simple computer-based task where they imagine walking through a room and press a button indicating if they can leave through a door on the left, center, or right wall. During or just before each of these tasks, participants will receive rTMS. In rTMS, a small plastic coil is placed next to the participant's head. The coil will be placed over the relevant brain region identified during the participant's fMRI scan. The coil will then generate a magnetic pulse, and stimulation will occur.

Repetitive Transcranial Magnetic Stimulation (rTMS) During Behavioral-based Task

Participants receiving rTMS while they perform behavioral-based tests to examine the causal involvement of OPA in visually-guided navigation. The study visit lasts approximately 90 minutes.

Group Type: EXPERIMENTAL

Repetitive Transcranial Magnetic Stimulation (rTMS)

Intervention Type: DEVICE

TMS is a safe and noninvasive method for affecting brain function relying on the properties of electromagnetic induction. Action potentials are triggered in neurons, along with a subsequent period of deactivation. Normal ongoing brain activity is disrupted providing a way for investigators to produce a transient and reversible period of brain disruption.

Behavioral-based Test

Intervention Type: BEHAVIORAL

Participants will be asked to complete a simple behavioral task that will require them to walk around in a small room and search for hidden objects. During or just before each of these tasks, participants will receive rTMS. In rTMS, a small plastic coil is placed next to the participant's head. The coil will be placed over the relevant brain region identified during the participant's fMRI scan. The coil will then generate a magnetic pulse, and stimulation will occur.

Interventions

Repetitive Transcranial Magnetic Stimulation (rTMS)

TMS is a safe and noninvasive method for affecting brain function relying on the properties of electromagnetic induction. Action potentials are triggered in neurons, along with a subsequent period of deactivation. Normal ongoing brain activity is disrupted providing a way for investigators to produce a transient and reversible period of brain disruption.

Intervention Type: DEVICE

Computer-based Test

Participants will be seated comfortably in a chair and asked to complete a simple computer-based task where they imagine walking through a room and press a button indicating if they can leave through a door on the left, center, or right wall. During or just before each of these tasks, participants will receive rTMS. In rTMS, a small plastic coil is placed next to the participant's head. The coil will be placed over the relevant brain region identified during the participant's fMRI scan. The coil will then generate a magnetic pulse, and stimulation will occur.

Intervention Type: BEHAVIORAL

Behavioral-based Test

Participants will be asked to complete a simple behavioral task that will require them to walk around in a small room and search for hidden objects. During or just before each of these tasks, participants will receive rTMS. In rTMS, a small plastic coil is placed next to the participant's head. The coil will be placed over the relevant brain region identified during the participant's fMRI scan. The coil will then generate a magnetic pulse, and stimulation will occur.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• Normal or corrected-to-normal vision

Exclusion Criteria

• Metal in the body
• Personal or first-degree family history of epileptic seizure
• A known brain injury
• Claustrophobia
• Taking certain medications that may increase the risk of seizures (e.g., bupropion, varenicline, chlorpromazine, theophylline) or reduce the effects of rTMS, such as benzodiazepines
• Adults who are unable to consent, pregnant women, and prisoners

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Eye Institute (NEI)

NIH

Sponsor Role: collaborator

Emory University

OTHER

Sponsor Role: lead

Responsible Party

Daniel Dilks

Associate Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Daniel Dilks, PhD

Role: PRINCIPAL_INVESTIGATOR

Emory University

Locations

Emory University

Atlanta, Georgia, United States

Countries

United States

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Document Type: Informed Consent Form

View Document

Other Identifiers

5R01EY029724

Identifier Type: NIH

Identifier Source: secondary_id

View Link

STUDY00002512

Identifier Type: -

Identifier Source: org_study_id