Effects of Transcranial Direct Current Stimulation on the right and left dorsolateral prefrontal cortex or Non-Invasive Vagus Nerve Stimulation in adults with Chronic Stress

Background: Chronic stress is a condition characterized by prolonged stimulation, leading to mental and physical weakness. It can have detrimental effects on individuals' mental health and cognitive function, potentially causing various health issues. Objective: This article explores the potential of noninvasive neuromodulation techniques, specifically transcranial direct current stimulation (tDCS) and transcutaneous auricular vagus nerve stimulation (taVNS), in managing chronic stress and improving sleep quality. Methods: The study conducted a randomized, double-blinded, controlled trial with participants experiencing chronic stress. In total, 100 participants were randomly assigned to the anodal tDCS group or the sham tDCS group, or taVNS group or the sham taVNS group, which received 5 sessions of the 20 min tDCS over the DLPFC (2 mA; n = 50) or taVNS on the left ear (20Hz; n=50), or the sham treatments. Stress, perceived stress and sleep quality were assessed at baseline, post intervention and four weeks after the intervention. Results: The tDCS and taVNS interventions resulted in reduced stress levels, improved sleep quality, and enhanced perception of stress. Conclusions:These findings suggest that tDCS and taVNS hold promise as effective treatments for chronic stress, offering a safe and accessible approach to improving individuals' well-being and overall quality of life.