Effort-based decision-making has been proposed as a potential mechanism contributing to transdiagnostic motivational deficits in psychotic disorder and bipolar disorder. However, very limited information is available about deficits in effort-cost-decision-making in the early stages of psychotic disorder and no study has investigated effort allocation deficits before the onset of bipolar disorder. Our aim was to investigate effort-based-decision-making in ultra-high-risk for psychosis (UHR-P) and bipolar disorder (UHR-BD).

Effort-cost decision-making performance was evaluated in UHR-P (n = 72) and UHR-BD (n = 68) and healthy controls (n = 38). Effort-Expenditure for Reward Task (EEfRT) was used.

Compared to controls, both UHR-P and UHR-BD groups were associated with a reduced possibility to choose the harder task when the reward magnitudes and/or the likelihood of receiving the reward were high. In both groups, effort allocation abnormalities were associated with poor social functioning.

The current findings suggest that difficulties in effort-cost computation are transdiagnostic markers of illness liability in psychotic and bipolar disorders. In early intervention services, effort-based decision-making abnormalities should be considered as a target for interventions to manage motivational deficits in individuals at high risk for psychosis and BD.