Recovery of Autonomous Balance as Indicator of Normalizing Effects of Non-invasive Vagus Stimulation

Clinical studies have shown the effectiveness of electrical stimulation for mental and stress-related disorders. We analysed the effects of novel transcutaneous vagus nerve stimulation (tVNS) for boosting mental and physical health and performance in work conditions. 62 healthy volunteers 18-49 years old were recruited for the study. The tVNS (BrainPatch platform for non-invasive stimulation) was arranged as a 4-day course of 6-minute stimulation sessions with monitoring of heart rate variability (HRV). Psychological testing (State Anxiety, STAI; psychological stress level, PSM-25; emotional burnout level MBI; identification of depression, IDS) was carried out on the first and last day of the study. We detected beneficial changes in the psychoemotional state of the respondents: improvement of mood, reduction of work stress (PSM-25), beneficial effects on emotional exhaustion and professional reduction (MBI), as well as on depression symptoms (IDS). HRV effects of VNS were observable and significant in short-term and reflected the activation of the parasympathetic nervous system ( the increase of vagally mediated parameter RMSSD and decrease of LF/HF ratio). An increase in the spectrum of high-frequency band indicates a high degree of recovery and readiness for stress. Our data suggests that the novel tVNS protocol attenuated the work related stress impacts. A normalizing effect of the tVNS on the psychoemotional state manifested in the form of shifting "sympatho-vagal balance" to the functional optimum.