Application of Noninvasive Vagal Nerve Stimulation to Stress-Related Psychiatric Disorders.

James Douglas Bremner,Bradley D Pearce,Matthew T Wittbrodt,Jeanie Park,Nil Z Gurel,Mobashir H Shandhi,Jonathon A Nye,Amit J Shah,Omer T Inan,Viola Vaccarino,Mark H Rapaport,Marom Bikson

doi:10.3390/jpm10030119

Abstract

Background: Vagal Nerve Stimulation (VNS) has been shown to be efficacious for the treatment of depression, but to date, VNS devices have required surgical implantation, which has limited widespread implementation. Methods: New noninvasive VNS (nVNS) devices have been developed which allow external stimulation of the vagus nerve, and their effects on physiology in patients with stress-related psychiatric disorders can be measured with brain imaging, blood biomarkers, and wearable sensing devices. Advantages in terms of cost and convenience may lead to more widespread implementation in psychiatry, as well as facilitate research of the physiology of the vagus nerve in humans. nVNS has effects on autonomic tone, cardiovascular function, inflammatory responses, and central brain areas involved in modulation of emotion, all of which make it particularly applicable to patients with stress-related psychiatric disorders, including posttraumatic stress disorder (PTSD) and depression, since dysregulation of these circuits and systems underlies the symptomatology of these disorders. Results: This paper reviewed the physiology of the vagus nerve and its relevance to modulating the stress response in the context of application of nVNS to stress-related psychiatric disorders. Conclusions: nVNS has a favorable effect on stress physiology that is measurable using brain imaging, blood biomarkers of inflammation, and wearable sensing devices, and shows promise in the prevention and treatment of stress-related psychiatric disorders.

Highlights

Stress-related psychiatric disorders, including depression and posttraumatic stress disorder (PTSD), are important public health problems
Noninvasive Vagal Nerve Stimulation devices include transcutaneous auricular VNS, which target the auricular branch of the vagus in the ear [262], and transcutaneous cervical VNS, which act on the cervical branch as it passes through the carotid sheath in the neck [100]
Neuromodulation is an important alternative treatment, and noninvasive forms of VNS have the advantages of cost and noninvasiveness and can potentially be widely implemented for these patients

Summary

Introduction

Stress-related psychiatric disorders, including depression and posttraumatic stress disorder (PTSD), are important public health problems. 10% of the United States population meets the criteria for major depression or other mood disorders based on Diagnostic and Statistical Manual (DSM) criteria [5], with an annual cost of lost productivity of USD 44 billion [6]. Depression is associated with depressed mood, loss of appetite, decreased psychomotor activity, and, in extreme cases, suicidal ideation. Other symptoms, such as poor sleep and concentration, negative cognitions, loss of interest in things, and anhedonia, are common to both conditions. Given limitations of current treatment options, new paradigms are clearly needed for the management of stress-related psychiatric disorders

Physiology of the Vagus Nerve

Neuromodulation for Stress-Related Psychiatric Disorders

Vagus Nerve and Neuroplasticity

Noninvasive Vagal Nerve Stimulation

Findings

Conclusions