Effort, Avolition, and Motivational Experience in Schizophrenia: Analysis of Behavioral and Neuroimaging Data With Relationships to Daily Motivational Experience

Recent research suggests that schizophrenia is associated with reduced effort allocation. We examined the willingness to expend effort, neural correlates of effort allocation, and the relationship of effort to daily motivational experience in individuals with schizophrenia. We recruited 28 individuals with schizophrenia and 30 control participants to perform an effort task during functional MRI. Individuals with schizophrenia also completed a protocol involving ecological momentary assessment (EMA). Individuals with schizophrenia with severe negative symptoms were less willing to expend effort for rewards. Daily EMAs of motivation were positively associated with effort allocation on a trend level. Individuals with schizophrenia and control participants displayed similar increases in blood-oxygen-level-dependent (BOLD) activation in frontal, cingulate, parietal, and insular regions during effort-based decision making. However, negative symptoms were associated with reduced BOLD activation in the bilateral ventral striatum. These results replicate previous reports of reduced effort allocation in patients with severe negative symptoms and provide evidence for the role of the ventral striatum in effort impairments.