Current Directions in the Auricular Vagus Nerve Stimulation I and II

Eugenijus Kaniusas, Stefan Kampusch, Marc Tittgemeyer, Fivos Panetsos, Raquel Fernandez Gines, Michele Papa, Attila Kiss, Bruno Podesser, Antonino Cassarà, Emmeric Tanghe, Amine Mohammed Samoudi, Thomas Tarnaud, Wout Joseph, Vaidotas Marozas, Arunas Lukosevicius, Niko Ištuk, Sarah Lechner, Wlodzimierz Klonowski, Giedrius Varoneckas, Constantin Szeles, and Antonio Šarolic, Frontiers in Neuroscience, section Neuroprosthetics, online 10 July 2019; doi: 10.3389/fnins.2019.00772

The two manuscripts summarize the results of two workshops on Auricular Vagus Nerve Stimulation (aVNS) held in Warsaw and in Vienna in 2017 within the framework of the EU COST Action “European network for innovative uses of EMFs in biomedical applications (BM1309)”.

The first paper (‘a physiological perspective’) summarizes physiological aspects of aVNS, including anatomical and electrophysiological description of the vagus Nerve (VN) and its auricular branch, and reports about aVN direct and indirect connections to other components of the peripheral nervous system. The biophysical mechanisms of aVNS are illustrated, as well as the mechanisms for which aVNS interfere with multiple body functions such as nociceptive processing, brain chemistry, inflammation response, and multiple systemic physiological parameters affecting respiration and blood flow.Results from multiple animal and human studies are reported and commented.

The second paper illustrates the current method to modulate the aVN function based on electric stimulation using percutaneous electrodes illustrating benefits and limitations of the method (e.g. in comparison with invasive VNS). Regulatory aspects are discussed for what concerns requirements that aVNS devices must comply in order to be conformal with EU directives for medical device. Then, technological challenges (such as optimization of stimulation parameters, placement of the electrodes, etc) are and solutions to address them are reported. These include personalization of treatment and the use of in silico investigations in combination with detailed anatomical model of the ear and neuroelectric models of the aVN to optimize stimulation settings,electrode geometries and positions, pulse waveform.