tDCS in People With Subthreshold Depression

This study is testing transcranial direct current stimulation (tDCS) — a non-invasive brain stimulation technique that passes a very mild electrical current through the scalp — in people with mild depressive symptoms that don't yet meet the full criteria for clinical depression (called "subthreshold depression"). The goal is to see whether tDCS can reduce these symptoms before they worsen. **You may be eligible if...** - You have mild depressive symptoms that qualify as "subthreshold depression" (below the level of a full clinical depression diagnosis) - You have no history of learning disabilities, major psychiatric disorders (including Major Depressive Disorder), or neurological conditions - You have completed at least primary school education **You may NOT be eligible if...** - You are currently on medications or undergoing treatments that affect brain or mood function (within the 2 weeks before the study) Talk to your doctor to see if this trial is right for you.