Reward processing plays a transdiagnostic role in the etiopathogenesis of psychopathology. Reinforcement learning deficits, driven by dopamine dysregulation, are hypothesized to explain key aspects of such abnormalities. Therefore, this project examines whether dopamine, assessed using neuromelanin-sensitive magnetic resonance imaging (NM-MRI), a novel imaging technique for assessing long-term midbrain dopamine function in the Substantia Nigra (SN) and Ventral Tegmental Area (VTA), contributes to reinforcement learning performance.