TACS on High-inflammatory and Refractory Depression

This study is testing transcranial alternating current stimulation (TACS) — a non-invasive brain stimulation technique that uses mild electrical currents on the scalp — as a treatment for people with depression that involves high levels of inflammation and has not responded to standard antidepressant medications. **You may be eligible if...** - You are between 18 and 55 years old - You have been diagnosed with depression by a psychiatrist using standard criteria (DSM-5) - Your depression score is 17 or higher on the Hamilton Depression Rating Scale - Your CRP level (a blood marker of inflammation) is between 0.85 and 10 mg/L - Your depression has not responded to at least some treatment (treatment-resistant) - You have been on a stable dose of antidepressants or antipsychotics for at least 2 weeks **You may NOT be eligible if...** - You have a history of epilepsy, seizures, brain tumors, or acute brain injury - You have metal implants in your head or a pacemaker - You are pregnant or breastfeeding - You have other major psychiatric diagnoses that would interfere with the study Talk to your doctor to see if this trial is right for you.