Non-invasive Vagus Nerve Stimulation as a Tool to Modulate Stomach-Brain Coupling in Depression

Summary

The overarching goal of the project is to determine whether differences in stomach-brain coupling contribute to key symptoms of major depressive disorder (MDD) and whether transcutaneous non-invasive vagus nerve stimulation (tVNS) may serve as a non-invasive intervention to improve aberrant interoceptive signaling in participants suffering from MDD.

Conditions

• Depressive Disorder, Major

Interventions

DEVICE

Transcutaneous non-invasive vagus nerve stimulation (tVNS)

Participants receive tVNS during the neuroimaging sessions and the extended stimulation period. To stimulate vagal afferents, the electrode will be placed at the cymba conchae of the right ear using a previously established, conventional stimulation protocol (25 Hz, 30s on/30s off cycle; NEMOS device, Cerbomed, Erlangen, Germany). To improve blinding, the stimulations intensities will be adjusted to correspond to a mild pricking sensation for tVNS and sham. The extended stimulation period in the experimental group involves six sessions with at least 1.5h of stimulation (stimulation in the lab or at home with home device using the same stimulation protocol as during the neuroimaging sessions; tVNS R device, tVNS Technologies GmbH, Erlangen, Germany).

DEVICE

Sham stimulation

The control intervention consists of a sham stimulation. In the neuroimaging session the electrode will be placed upside down to stimulate the earlobe, which is not innervated by vagal afferent fibers. To improve blinding, the same stimulation protocol as for the tVNS will be applied (25 Hz, 30s on/30s off cycle; NEMOS device, Cerbomed, Erlangen, Germany) and stimulation intensities will be adjusted to correspond to a mild pricking sensation. During the extended stimulation period, the electrode will be placed at the cymba conchae, but only receive a low-intensity stimulation below the perception threshold (0.1mA). To ensure blinding, participants will be instructed that the extended stimulation period will examine the effects of a low- vs. high-intensity tVNS protocol. Each repeated stimulation period will involve six sessions with at least 1.5h of low-intensity stimulation (stimulation in the lab or at home with home device; tVNS R device, tVNS Technologies GmbH, Erlangen, Germany).

Sponsors & Collaborators

• University Hospital Tuebingen

  collaborator OTHER

• University of Bonn

  lead OTHER

Principal Investigators

• Nils B Kroemer, Prof. · Section of Medical Psychology, Department of Psychiatry & Psychotherapy, Faculty of Medicine, University of Bonn, 53127 Bonn, Germany

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

55 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2024-05-21

Primary Completion

2026-12-31

Completion

2026-12-31

Countries

• Germany

Study Locations