Effort-Based Decision Making and Motivated Behavior in Everyday Life

点击翻译按钮获取中文摘要

Motivational impairments are a key feature of both psychotic and mood disorders. Decreases in motivation impair work and social function transdiagnostically, reduce quality of life, and increase public health demands. Current treatments are not sufficiently effective at reducing impairments in motivation, in part due to the need to better understand the mechanisms that give rise to these symptoms. The work in the prior round of funding provided strong evidence that abnormal effort-cost decision-making (ECDM; Effort valuation/Willingness to work in the RDoC Positive Valence System) may be a key contributor to motivational deficits in psychotic pathology (i.e., individuals with schizophrenia, schizoaffective disorder and bipolar disorder), but not among individuals with mood pathology (i.e., Major Depression). ECDM refers to calculations that individuals perform to estimate the amount of physical or cognitive "work" required to obtain a reward. Individuals with schizophrenia, schizoaffective, bipolar disorder are less motivated than healthy individuals to exert effort to obtain rewards on experimental tasks of ECDM, with associated deficits in dorsal-fontal parietal control systems, and these deficits are related to symptoms of amotivation and function in everyday life. Individuals with depression did not show such deficits on tasks of either physical or cognitive effort, despite showing clear evidence of anhedonia in everyday life. These data strongly support our hypotheses that the mechanisms that contribute to motivational impairments in psychosis differ from those in depression. Here we expand this work. In Aim 1 we will utilize novel behavioral and imaging paradigms derived from the affective science literature to assess social and non-social motivation (Consultant Sommerville, co-I Braver) to test the hypothesis that individuals with psychosis will show even greater impairment in effort allocation for social than monetary rewards, while individuals with depression will show equal impairments in both. In Aim 2, we will integrate state-of-the art neuroimaging methods (neuromelanin) to indirectly measure dopamine function (consultant Horga) to test the hypothesis that dopamine disruption will be more strongly related to indices of motivational impairments in depression versus psychosis. In Aim 3, we will incorporate innovative mobile technologies to longitudinally assess social and non-social motivated behavior and cognition (Consultant Gershon) in everyday life, testing the hypotheses that the magnitude of motivational impairments in psychosis will covary over time with cognitive impairments among individuals with psychosis, but not among individuals with depression.