Microelectrode Recordings From the Vagus Nerve in Awake Humans

NCT ID: NCT06016686

Last Updated: 2025-04-22

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: PHASE1
• Total Enrollment: 60 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-04-01
• Study Completion Date: 2026-04-01

Brief Summary

This Anchillary project uses a refined technique of ultrasound-guided microneurography of the human cervical vagus nerve, an approach developed by Professor Vaughan Macefield and used safely to-date in 44 prior study participants.

The overall goal of this project is to build upon prior data obtained using this approach by undertaking a detailed neurophysiological investigation of the human vagus nerve and to identify the nerve fibers activated during vagal nerve stimulation (VNS) in participants with implanted VNS devices in response to different stimulation parameters. In addition to providing data in unprecedented detail into the physiology of the human vagus nerve, this project will investigate different stimulus intensities, durations and frequencies that differentially excite myelinated and unmyelinated nerve fibers. These results will inform the CSP and guide future development of novel neural interfaces for VNS for various clinical applications.

Conditions

Epilepsy

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: SUPPORTIVE_CARE
• Blinding Strategy: NONE

Study Groups

VNS

participants with surgically implanted VNS electrodes to treat drug-resistant epilepsy

Group Type: EXPERIMENTAL

VNS stimulation and intraneural recordings

Intervention Type: OTHER

A minimum of three stimulation frequencies (1, 10 and 30 Hz), each up to 60s in duration, will be delivered via the VNS device. Intraneural recordings proximal or distal to the VNS electrodes during delivery of VNS will be performed. Approximately two to five fascicles will be explored in each nerve.

non-VNS participants

participants without implanted VNS devices

Group Type: EXPERIMENTAL

Record multi-unit activity from intraneural sites

Intervention Type: OTHER

Perform a more detailed vagal nerve mapping study by recording from single nerve fibers, including those fibers supplying the heart, lungs, airways and other end-organs. The investigators shall perform functional mapping of the left and right vagus nerves, such as those with cardiac-related and/or respiratory-related neural activity. The research team will also record activity from other nearby fibers to map the differences in neurological behavior in fascicles that control the heart, lungs, airways and other systems.

Interventions

VNS stimulation and intraneural recordings

A minimum of three stimulation frequencies (1, 10 and 30 Hz), each up to 60s in duration, will be delivered via the VNS device. Intraneural recordings proximal or distal to the VNS electrodes during delivery of VNS will be performed. Approximately two to five fascicles will be explored in each nerve.

Intervention Type: OTHER

Record multi-unit activity from intraneural sites

Perform a more detailed vagal nerve mapping study by recording from single nerve fibers, including those fibers supplying the heart, lungs, airways and other end-organs. The investigators shall perform functional mapping of the left and right vagus nerves, such as those with cardiac-related and/or respiratory-related neural activity. The research team will also record activity from other nearby fibers to map the differences in neurological behavior in fascicles that control the heart, lungs, airways and other systems.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• The participant is greater than or equal to (≥)18 years and is less than or equal to (≤) 40 years of age
• English speaking
• Medicare covered or equivalent health insurance from a partner country

Exclusion Criteria

• Pregnant
• Smokes and is unwilling to abstain from smoking on the day of the experiment.
• Inability or unwillingness to provide written informed consent.
• Individuals with difficulty standing unassisted for 5 minutes during the tilt-table testing
• Individuals found to have a significant carotid artery plaque or intima-media thickness > 1 mm as assessed by ultrasonography during the ultrasound-screening steps of the study visit
• Vagus nerve not visible on ultrasound
• VNS electrodes are not in a suitable location to allow for microelectrode insertion
• Any other clinical reasons deemed by the investigators

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 40 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Minnesota

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Vaughan G Macefield, PhD

Role: PRINCIPAL_INVESTIGATOR

Monash University

John Osborn

Role: PRINCIPAL_INVESTIGATOR

University of Minnesota

Locations

University of Minnesota

Minneapolis, Minnesota, United States

Site Status: RECRUITING

99 Commercial Road

Prahan Victoria, , Australia

Site Status: RECRUITING

Countries

United States; Australia

Central Contacts

Kathryn Vera, PhD

Role: CONTACT

giero002@umn.edu

612-625-5018

Facility Contacts

Kathryn Vera, PhD

Role: primary

giero002@umn.edu

612-625-5018

Vaughan G Macefield, BSc(Hons) PhD DSc FAAS

Role: primary

vaughan.macefield@monash.edu

+61 (0)426 581 647

Other Identifiers

VNS

Identifier Type: -

Identifier Source: org_study_id