Neurobiological Mechanisms of Pathological Rumination and Effects of Aripiprazole

Escitalopram will be administered orally at a fixed dose of 20 mg/day for 8 weeks. This SSRI antidepressant is used as baseline pharmacological treatment for patients with major depressive disorder (MDD), either as monotherapy or in combination with aripiprazole. No other psychotropic medications are allowed during the study period.

Aripiprazole will be administered as an adjunctive treatment to escitalopram at an initial dose of 2.5 mg/day, titrated up to 5 mg/day based on tolerability. Treatment will last 8 weeks, after which aripiprazole will be tapered and discontinued. This intervention aims to evaluate the efficacy of dopaminergic augmentation in reducing pathological rumination symptoms.