Vagus Nerve Stimulation to modulate Inflammation

Non-invasive tVNS to Improve Inflammatory Processes (Neuro-acsis)

Status: The study is currently ongoing. We are seeking participants with a slightly raised BMI (overweight). All appointments will take place at the University Hospital Bonn, and you can contact us immediately.

Summary of key information

  • Increased body weight can promote inflammation. Initial studies show that vagus nerve stimulation triggers anti-inflammatory processes in the body. Additionally, it can improve motivation and mood. To advance its use as a therapy, we are investigating this relationship.
  • For this study, we are looking for healthy individuals who have a slighlty raised BMI (BMI 27–35 kg/m²). The study consists of four sessions, and full participation takes up to 10 hours. You will receive a stimulation device to take home for use over several weeks. As compensation for your time, you will receive €100 for full participation in the study, including approximately €20 in rewards from the behavioral tests.
  • If you are interested in participating in this study, you will find all essential information on this page. Please send us a message via the contact form. We will then be happy to get in touch with you and discuss the next steps.

Your Study Team

Study Doctor: Dr. med. Luisa Kaluza

Data Protection: The data you provide in the form will be processed by us exclusively for the purpose of responding to or implementing your request, contacting you, and providing you with direct access to the game. For processing, we refer to Art. 6 (1) (a) DSGVO, unless another legal basis applies. Your data will not be passed on to third parties. You can revoke your consent at any time with effect for the future. In the event of revocation, your data will be deleted immediately. Otherwise, your data will be deleted once we have processed your request or the purpose of storage no longer applies.

Summary

The vagus nerve plays an essential role in transmitting signals between the body and the brain. Its role in regulating inflammatory processes and motivation has been well studied in animal models.

There is also evidence that increased inflammation in the body is associated with changes in motivation and mood and may contribute to the development of conditions such as depression or diabetes.

In this study, we are investigating whether and to what extent non-invasive vagus nerve stimulation in humans can influence inflammatory parameters and reward processing. To this end, we will measure various inflammatory parameters in the blood and use modern imaging techniques combined with innovative behavioral tests. As a participant, you will have the opportunity to stimulate your vagus nerve non-invasively in your daily life.

We expect this study to provide important insights into the link between metabolic disorders and motivational changes. These findings could further the development of innovative therapeutic approaches.

Study Information

Who can participate?
Please contact us if you are between the ages of 18 and 40 and have a BMI between 27 kg/m² and 35 kg/m². We will discuss all further details with you during a preliminary phone call. We would also be happy to provide you with information about other study options.
How many sessions are included in the study?
The study consists of a total of 4 in-person sessions. The first, second, and fourth sessions will each last around 3 hours, while the third session will last around 1 hour.
Why should I participate? Will I receive compensation?
Participation in the study is voluntary. However, we can compensate you for your time. Full participation in the study is compensated with €80; in addition, you can win approximately €20 (typically between €10 and €30, depending on your decisions) in the behavioral tests.
What does participation in this study involve?
We will ask you to attend the appointments fasted. First, we will collect some basic information, such as your height and weight, and take a blood sample. Next, we will assess your mood using a computer-based questionnaire. After that, you will perform a behavioral task inside the MRI scanner. We will also conduct a clinical interview and ask you to complete questionnaires about your eating habits, general motivation, and personality. Finally, we will provide you with a device to stimulate your vagus nerve at home.

How should you prepare for your study appointments?
Since we are also investigating certain aspects of metabolism, it is important that you arrive fasted. Therefore, please do not eat or drink any calorie-containing beverages for approximately 12 hours prior to your study appointment. In addition, because we would like to measure inflammation in your body, please avoid taking common pain medications (e.g., ibuprofen, Novalgin, acetaminophen), which can affect inflammation, for three days prior to your appointment, as these can affect inflammation levels.

What is vagus nerve stimulation?
What makes this study unique is that we use an external device to stimulate the vagus nerve at the ear with electrical impulses.The vagus nerve is a cranial nerve that transmits signals from many internal organs to the brain. A portion of the vagus nerve runs near the ear and can be specifically targeted through electrical stimulation. Vagus nerve stimulation is an established therapeutic procedure and is currently used primarily in the treatment of epilepsy and depression. A new generation of devices now enables non-invasive stimulation at the ear. The stimulation electrode is shaped like a headphone and can be attached to the right ear.

Are there any side effects associated with non-invasive vagus nerve stimulation?
Initial clinical studies have confirmed that the procedure is generally tolerated very well. Depending on the stimulation intensity, you may experience a mild tingling sensation at the stimulation site. The stimulation intensity will be individually adjusted to ensure that it is not painful.
According to the device manufacturer (tVNS TECHNOLOGIES), possible side effects include mild stinging or slight discomfort at the stimulation site.
Because stimulation of the vagus nerve can also affect the autonomic nervous system, some people may experience temporary headaches, nausea or dissiness.
In rare cases the stimulation may affect the cardiovascular system. This can result in bradycardia (slowed heart rate) and a sudden drop in blood pressure (shock). If this side effect occurs, it can be resolved by quickly repositioning the patient. These side effects disappear quickly once the stimulation is stopped. No long-term side effects are currently known in physically healthy individuals. We will assess your suitability for vagus nerve stimulation on an individual basis before the study begins and monitor any potential side effects that may occur during your participation in direct consultation with our study physician.

What is magnetic resonance imaging (MRI)?
In this study, we also aim to gather information about the processes occurring in the brain, and we use magnetic resonance imaging (MRI) to do so. MRI is a medical imaging technique used to visualize organs and tissues, but it relies on magnetic fields and radio waves that are imperceptible to the body. Images of the head are generated based on the interaction between these magnetic fields and radio waves.

Magnetic Resonance Imaging (Example)
Where can I learn more about the study and the potential risks?
If you are interested in participating, we will talk you through the detailed informed consent form; we will send this to you in advance via email. We are happy to answer any questions you may have about potential risks and the study’s objectives. Please feel free to contact us at any time if you have questions. Once all your questions have been answered, you will sign the participant information form before your first appointment. This confirms that your participation is voluntary.