Episodic processes in moral decisions: Evidence from medial temporal lobe amnesia

Theoretical accounts of moral decision making imply distinct ways in which episodic memory processes may contribute to judgments about moral dilemmas that entail high conflict between a harmful action and a greater good resulting from such action. Yet, studies examining the status of moral judgment in amnesic patients with medial temporal lobe (MTL) lesions have yielded inconsistent results. To examine whether and how episodic processes contribute to high conflict moral decisions, amnesic patients with MTL damage and control participants were asked to judge the moral acceptability of a harmful action across two conditions that differed in the framing of the moral question. We predicted that personal (but not abstract) framing would engage episodic processes involved in mental simulation, yielding a selective impairment in MTL patients in the personal framing condition. This prediction was not confirmed as neither patients nor controls were influenced by the framing of the moral question. With the exception of a patient whose lesion extended into the amygdala bilaterally, patients were less willing than controls to endorse the utilitarian option, rejecting the harmful action despite its beneficial outcome. They also rated actions as emotionally more intense than did controls. These findings suggest that episodic processes involved in mental simulation are necessary to prospectively evaluate action-outcome contingencies.