Increasing resilience to stress by home-based transcranial stimulation.

Mental health disorders, especially anxiety and depression, affect nearly one billion people worldwide, with chronic stress playing a major role in their onset and severity. Despite growing demand, access to care remains limited, underscoring the need for scalable, preventive interventions. This study investigates the feasibility, safety, and preliminary effects of a Home-Based transcranial Direct Current Stimulation (HB-tDCS) protocol targeting the left dorsolateral prefrontal cortex (L-DLPFC) to enhance stress resilience in healthy middle-aged adults. Thirty-one participants completed ten sessions of self-administered tDCS over two weeks, monitored remotely. Adherence was high (98 %), with minimal technical issues and no serious adverse events reported. Mild, transient side effects occurred in only four participants. A stress induction paradigm involving pupillometry, electrodermal activity (EDA), and subjective stress and anxiety ratings was administered pre- and post-intervention. Results indicated a significant reduction in acute stress appraisal, but no significant changes in anxiety scores or physiological markers. These findings support the feasibility and safety of HB-tDCS and suggest potential stress-reducing effects, though the absence of a control group and limited psychophysiological impact warrant cautious interpretation. Future research should explore longer stimulation protocols, controlled trials, and clinical applications in populations with heightened stress vulnerability.