Bipolar disorder (BP) is characterized by altering states of depression and mania. During these episodes, psychotic symptoms such as delusions and hallucinations can emerge. BP patients can...Show moreBipolar disorder (BP) is characterized by altering states of depression and mania. During these episodes, psychotic symptoms such as delusions and hallucinations can emerge. BP patients can experience reward learning impairments and social deficits, which have been proved to be influenced negatively by psychotic symptoms. To identify more underlying structures of BP, this study examined reward valuation (the process of evaluating and comparing rewards corresponding with different options), the influence of psychotic symptoms on reward valuation and the relationship between social reward valuation and sensitivity for positive feedback. This study was a cross-sectional, observational study with a case-control and correlational design. From the Positive Valence study, a total of 19 patients and 17 controls were included. Reward valuation was measured with two multi-armed bandit tasks (a monetary- and social reward condition). Psychotic symptoms were measured with the Comprehensive Assessment of Symptoms and History, the MINI Internationaal Neuropsychiatrisch Interview 5.0.0. and the Basis-24 questionnaire. Social deficits were explored by examining the relationship between total social bandit score and the ‘positive feedback’ score of the Positive Valence Systems Scale. We carried out Mann-Whitney U tests and linear regressions. Results showed no significant differences in total monetary bandit score (U = 138, z = .072, p = .958), and total social bandit score (U = 183, z = .682, p = .510) between patients and controls. Moreover, there was no significant difference in total monetary bandit score (U = 39, z = -1.398, p = .176) and total social bandit score (U = 80, z = -1.023, p = .982) between the participants with and without psychotic symptoms. In addition, total social bandit score was not significantly related to sensitivity for positive feedback (F(1, 32) = 1.457, p = .236). This study found no significant between-group differences in reward valuation and no relationship between social reward valuation and sensitivity for positive feedback, indicating that (social) reward valuation processes possibly differ from other reward processes in this population. Considering the limitations, this study contributed to improving our current taxonomy, highlighting the importance of taking subconstructs and personal differences into account with diagnostics and treatment.Show less
