Multiple Sclerosis (MS) is a chronic, progressive disease that affects young adults (aged between 20 and 40) and has a major impact on patients' quality of life. Cognitive disorders in MS are common, affecting 40-60% of patients. Among these disorders, the presence of social cognition disorders is common. Within social cognition, the moral judgment has been an object of research in order to understand the determinants of moral decision-making: how and why individuals make moral choices with regard to a set of prescriptions and social norms. Compared to control subjects, MS patients show a decrease in moral permissiveness, as well as an increase in moral relativity and emotional reactivity. Thus, it would seem that MS patients issue more deontological choices (lower moral permissiveness). Given that these patients also exhibit empathy deficits and higher alexithymia, these patterns are surprising. Indeed, in other clinical populations, low empathic abilities and high alexithymia are linked to utilitarian rather than deontological moral judgments. The objective of this project is to analyze the process of decision-making carried out by patients during moral dilemma situations in comparison with control individuals and verify whether the presence of a positivity bias could explain the more deontological choices made by some patients. Indeed, some work has shown that older individuals make more deontological moral judgments than younger adults. These results are also observed with young individuals when their future temporal perspectives have been experimentally constrained.