Harming Kin to Save Strangers: Further Evidence for Abnormally Utilitarian Moral Judgments after Ventromedial Prefrontal Damage

Abstract

The ventromedial PFC (vmPFC) has been implicated as a critical neural substrate mediating the influence of emotion on moral reasoning. It has been shown that the vmPFC is especially important for making moral judgments about "high-conflict" moral dilemmas involving direct personal actions, that is, scenarios that pit compelling utilitarian considerations of aggregate welfare against the highly emotionally aversive act of directly causing harm to others [Koenigs, M., Young, L., Adolphs, R., Tranel, D., Cushman, F., Hauser, M., et al. Damage to the prefrontal cortex increases utilitarian moral judgments. Nature, 446, 908-911, 2007]. The current study was designed to elucidate further the role of the vmPFC in high-conflict moral judgments, including those that involve indirect personal actions, such as indirectly causing harm to one's kin to save a group of strangers. We found that patients with vmPFC lesions were more likely than brain-damaged and healthy comparison participants to endorse utilitarian outcomes on high-conflict dilemmas regardless of whether the dilemmas (1) entailed direct versus indirect personal harms and (2) were presented from the Self versus Other perspective. In addition, all groups were more likely to endorse utilitarian outcomes in the Other perspective as compared with the Self perspective. These results provide important extensions of previous work, and the findings align with the proposal that the vmPFC is critical for reasoning about moral dilemmas in which anticipating the social-emotional consequences of an action (e.g., guilt or remorse) is crucial for normal moral judgments [Greene, J. D. Why are VMPFC patients more utilitarian?: A dual-process theory of moral judgment explains. Trends in Cognitive Sciences, 11, 322-323, 2007; Koenigs, M., Young, L., Adolphs, R., Tranel, D., Cushman, F., Hauser, M., et al. Damage to the prefrontal cortex increases utilitarian moral judgments. Nature, 446, 908-911, 2007].