Sex Differences in Model free and Model based Behavior

Despite men and women nearing equal opportunities in education and career, we continue to identify sex-differences in decision-making. For instance, more women are found in social fields as nursing and medicine. One existing study found higher model-free behavior in the two-step task in women and another study found model-free behavior to be associated with prosocial behavior. We conducted an exploratory analysis to see (1) whether women differ regarding model-free and model-based behavioral control from men; (2) what brain responses underlie such differences. Participants (total 98; 37 female) performed the two-stage Markov task while in the fMRI scanner. Our analysis confirmed a previous finding of increased model-free behavior in women and we additionally observed an increased neural response in dorsolateral prefrontal cortex in women following not rewarded compared to rewarded trials. This difference was not present in men. Different decision-making patterns and neural responses observed between sexes in the two-step task are possibly able to predict existing real-world behavioral differences between men and women.