Yes, they can! Efficient physical effort mobilization according to task difficulty in schizophrenia

The current literature has largely highlighted a deficit of effort-based decision-making for reward in schizophrenia. However, not all studies have dissociated effort from reward, while other studies emphasize that difficulty is the main determinant of effort rather than reward. In this study, 33 individuals with schizophrenia and 32 healthy controls were recruited to perform a decision-making isometric force task. According to motivational intensity theory, task difficulty (i.e., required force) but not reward was manipulated from easy to impossible. Accuracy between force exerted and force required, and choice to perform a task or not were our effort measures. Clinical variables including depression, defeatist beliefs, and apathy were assessed. Our results demonstrated that the schizophrenia group chose to perform easy, moderate, and difficult tasks and exerted the necessary effort to succeed similarly to the non-clinical group. No association between effort and clinical variables was found. Our findings provide new understandings related to effort mechanisms in schizophrenia.