Transcutaneous Vagus Nerve Stimulation


VNS Device


Ear Clip Electrode

Anxiety Disorder




We are investigating into the treatment of Anxiety Disorders using Transcutaneous Vagus Nerve Stimulation, a non-invasive alternative treatment.

Research has found that stimulating the Vagus Nerve activates the parasympathetic nervous system and may be a promising, safe and cost effective therapeutic method for reducing anxiety.  

Non-invasive vagus nerve stimulation


The Parasym device non-invasively stimulates the Vagus Nerve.


This is done using a specially designed unit and ear-clip electrode.


Small micro-pulses of electricity are sent from the device to the Vagus Nerve, through the electrode.


On the treatment of anxiety disorders using Vagus Nerve Stimulation


autonomic nervous system


Parasympathetic and Sympathetic



Kraus, T., Hösl, K., Kiess, O., Schanze, A., Kornhuber, J., & Forster, C. (2007). BOLD fMRI deactivation of limbic and temporal brain structures and mood enhancing effect by transcutaneous vagus nerve stimulation. Journal of neural transmission, 114(11), 1485-1493.


“tVNS fMRI in healthy volunteers - Increased well being and hypoactivity (decrease)  in brain areas associated with anxiety and depression”


George, M. S., Sackeim, H. A., Rush, A. J., Marangell, L. B., Nahas, Z., Husain, M. M., ... & Ballenger, J. C. (2000). Vagus nerve stimulation: a new tool for brain research and therapy∗. Biological psychiatry, 47(4), 287-295.


HPA Axis


O’Keane, V., Dinan, T. G., Scott, L., & Corcoran, C. (2005). Changes in hypothalamic–pituitary–adrenal axis measures after vagus nerve stimulation therapy in chronic depression. Biological psychiatry,



VNS may change the encoding of negative memories


Critchley, H. D., Lewis, P. A., Orth, M., Josephs, O., Deichmann, R., Trimble, M. R., & Dolan, R. J. (2007). Vagus nerve stimulation for treatment-resistant depression: behavioural and neural effects on encoding negative material.Psychosomatic medicine,


Pardo, J. V., Sheikh, S. A., Schwindt, G. C., Lee, J. T., Kuskowski, M. A., Surerus, C., ... & Rittberg, B. R. (2008). Chronic vagus nerve stimulation for treatment-resistant depression decreases resting ventromedial prefrontal glucose metabolism. Neuroimage,  (non support)


Capone, F., Assenza, G., Di Pino, G., Musumeci, G., Ranieri, F., Florio, L., ... & Di Lazzaro, V. (2015). The effect of transcutaneous vagus nerve stimulation on cortical excitability. Journal of Neural Transmission,


“Our findings confirm that tVNS is a safe and effective way to stimulate vagus nerve”


Inoue, T., Abe, C., Sun-sang, J. S., Moscalu, S., Jankowski, J., Huang, L., ... & Okusa, M. D. (2016). Vagus nerve stimulation mediates protection from kidney ischemia-reperfusion injury through α7nAChR+ splenocytes. The Journal of clinical investigation,


Clancy, J. A., Mary, D. A., Witte, K. K., Greenwood, J. P., Deuchars, S. A., & Deuchars, J. (2014). Non-invasive vagus nerve stimulation in healthy humans reduces sympathetic nerve activity. Brain stimulation,


Frangos, E., Ellrich, J., & Komisaruk, B. R. (2015). Non-invasive access to the vagus nerve central projections via electrical stimulation of the external ear: fMRI evidence in humans. Brain stimulation,


“central projections of the ABVN are consistent with the “classical” central vagal projections and can be accessed non-invasively via the external ear.”


Kinfe, T. M., Pintea, B., Muhammad, S., Zaremba, S., Roeske, S., Simon, B. J., & Vatter, H. (2015). Cervical non-invasive vagus nerve stimulation (nVNS) for preventive and acute treatment of episodic and chronic migraine and migraine-associated sleep disturbance: preliminary findings from a prospective observational cohort study. The journal of headache and pain,


Kreuzer, P. M., Landgrebe, M., Husser, O., Resch, M., Schecklmann, M., Geisreiter, F., ... & Langguth, B. (2012). Transcutaneous vagus nerve stimulation: retrospective assessment of cardiac safety in a pilot study.Frontiers in psychiatry,


Clancy, J. A., Mary, D. A., Witte, K. K., Greenwood, J. P., Deuchars, S. A., & Deuchars, J. (2014). Non-invasive vagus nerve stimulation in healthy humans reduces sympathetic nerve activity. Brain stimulation,




Our autonomic nervous system (ANS) is a control system that acts largely unconsciously and is responsible for the regulation many of our bodily functions. Is has two branches that work in opposition to one another to create a balance, these are the parasympathetic nervous system and the sympathetic nervous system.


The sympathetic nervous system is often considered the 'fight or flight' system, while the parasympathetic is referred to as the 'rest and digest' system. Many serious health conditions have been linked to an overactive sympathetic nervous system (high stress), where the ANS is out of balance.  


The vagus nerve is linked to the parasympathetic branch of the ANS and by stimulating it, it is possible to reduce sympathetic activity and restore natural balance in the body needed for optimal health.