 Schizophrenia SC is associated with cognitive impairment in a variety of domains, including learning and memory. The neural underpinnings of these cognitive deficits, however, are poorly understood. Based on evidence that abnormal functioning of brain dopamine DA systems is implicated in both schizophrenia and mechanisms of reinforcement processing, we proposed to test theories of the functional role of dopamine in schizophrenia. Specifically, the studies described here test two main ideas about DA function and its possible contribution to SC: 1 its role in facilitating learning of cue-reward associations; and 2 its role in signaling mismatches between expected and experienced outcomes called prediction errors. 