Choosing the lesser evil: Electrophysiological correlates of moral judgment

Recent fMRI evidence suggests that emotional activation competes with cognitive con-trol in the resolution of moral dilemmas. However, little is known on the temporaldynamics of the emotional processes involved in moral cognition. The present study wasaimed at investigating the time course of neural processes associated with decision-making in moral judgment, by employing dilemmas in which subjects were required todecide between options A (letting a specific number of people die) and B (killing oneperson to save a specific number of people). Thirty-seven participants were presentedwith 60 dilemmas that orthogonally varied intentionality of the action (killing as a‘‘means’’ vs. ‘‘side-effect’’) and personal involvement (killing to save ‘‘oneself and oth-ers’’ vs. ‘‘others’’). Event-related potentials (ERPs) were recorded to a slide displayingthe letters ‘‘A’’ and ‘‘B’’, as subjects were deciding. Response choices and response timeswere also recorded. Ratings of valence and arousal experienced during decision-makingwere collected after each dilemma. As compared with ‘‘side-effect dilemmas’’, ‘‘meansdilemmas’’ prompted a lower number of B choices and longer response times. Further-more, they were rated as more unpleasant and arousing. ERP analysis revealed a sig-nificantly larger early P3 component in the frontal area when subjects were deciding on‘‘means’’ than on ‘‘side-effect dilemmas’’. This might reflect emotion-related conflictdetection and conflict resolution processes during the early stages of decision-making.