title: Schizophrenia subjects show intact success-related neural activation but impaired uncertainty processing during decision-making.
abstract: Decision-making is a complex process that is important for everyday life. This study examined the effect of the degree of success, and outcome uncertainty, on decision-making and associated neural substrate activation in schizophrenia subjects (SZS) and normal comparison subjects (NCS). A total of 15 subjects with a diagnosis of schizophrenia and 15 age- and education-matched NCS participated in this study. These subjects completed the two-choice prediction task during functional magnetic resonance imaging. Decision-making characteristics and activation of neural substrates were obtained at 20, 50, or 80% error rate. Success and uncertainty influenced the behavioral characteristics on the two-choice prediction task, and the task-related activation in SZS and NCS. Neither success nor uncertainty differentially affected the behavioral characteristics of SZS relative to NCS during the two-choice prediction task. Nonetheless, there was a significant interaction between group and error rate in bilateral parietal cortex. The activation in NCS was the highest when the outcome was most uncertain. In contrast, task-related activation in SZS was not modulated by the degree of uncertainty. Thus, SZS failed to utilize the parietal cortex to process decision-making situations with highly uncertain outcomes.
authors.affiliation: Laboratory of Biological Dynamics and Theoretical Medicine, University of California at San Diego, La Jolla, CA, USA. martin@mag.ucsd.edu
authors.forename: Martin P
authors.initials: MP
authors.lastname: Paulus
authors.forename: Lawrence
authors.initials: L
authors.lastname: Frank
authors.forename: Gregory G
authors.initials: GG
authors.lastname: Brown
authors.forename: David L
authors.initials: DL
authors.lastname: Braff
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002755:Choice Behavior / Q000502:physiology*; D003657:Decision Making / Q000502:physiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010296:Parietal Lobe / Q000502:physiology*; D012559:Schizophrenia / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D035501:Uncertainty