Home-Based tDCS for Depression in BPD

The present study aims to assess the feasibility of home-based tDCS in remote and urban areas (primary objective). The secondary aim is to obtain a preliminary assessment of the efficacy of 14 home-based tDCS sessions in reducing depressive symptoms in BPD patients with moderate to severe depressive episodes and BPD symptoms. Exploratory objectives include assessing the impact on neuropsychological and psychosocial functioning, anxiety, physical activity, sleep disorders, and addiction. Additionally, we aim to investigate the sociodemographic and clinical factors that are linked to the most favorable response to tDCS in addressing both depressive and BPD symptoms. We also aim to assess the feasibility of using a smartwatch as an outcome measure in this population. Finally, we intend to gather preliminary data on the effectiveness of an online psychoeducational program specifically designed for patients with BPD. Researchers will compare active tDCS to sham tDCS to see if active treatment is more effective in treating depression in this population. Participants will: * Receive 14 sessions of either active or sham tDCS over one week, delivered at home * Complete psychological and neurocognitive assessments at baseline, post-treatment, and at 6 weeks * Wear actigraphy monitors and complete questionnaires to assess sleep, physical activity, and other mental health outcomes This trial will also explore the feasibility of delivering tDCS in both urban and rural settings.