Manic patients exhibit more utilitarian moral judgments in comparison with euthymic bipolar and healthy persons

Abstract

Both emotional and cognitive processes are involved in moral judgments. Ventromedial prefrontal lesions are related to impaired prosocial emotions and emotional dysregulation, and patients with these lesions exhibit increased utilitarian judgments of emotionally salient personal moral dilemmas. Bipolar patients experiencing manic episode also have impaired emotional regulation and behavioral control. We investigated the characteristics of moral judgment in manic and euthymic patients with bipolar disorder using the 50 hypothetical moral dilemma task (17 non-moral, 20 personal, and 13 impersonal). Our study included 27 manic bipolar patients, 26 euthymic bipolar patients, and 42 healthy controls. Subjects were instructed to determine whether or not each dilemma was morally acceptable, and their reaction times were recorded. Manic patients showed significantly greater utilitarian judgment than euthymic patients and normal controls for personal moral dilemmas. However, there were no significant between-group differences for the non-moral and impersonal moral dilemmas. Our results suggest that increased utilitarian judgments of personal moral dilemmas may be a state-related finding observed only in manic patients. This difference in moral judgment assessments may reflect the decision-making characteristics and underlying neurobiological mechanisms of bipolar disorder, especially during the manic state.