Moral judgments by individuals with psychopathic traits: An ERP study

Psychopathy is a recognized risk factor for moral violations, but the mechanism of that increased risk is not well understood. Here, we used event-related potentials (ERPs) to investigate how psychopathic traits were related to the temporal dynamics of moral judgments when participants were asked to give moral acceptability ratings during the visual presentation of short statements with or without moral content. As expected, the ratings results showed that individuals with elevated psychopathic traits expressed increased acceptability of harm- and fairness-related moral violations. In contrast to that, ERP results were mixed. Regardless of subjects’ levels of psychopathic traits, both types of moral violations (harm and fairness) evoked larger early potentials (P2) than did neutral statements. Likewise, all participants, regardless of psychopathic traits, displayed greater late positive components (LPC) for harm-related moral statements compared to neutral statements. However, in one early component (N2), only individuals with lower psychopathic traits displayed greater sensitivity to fairness- than to harm-related moral violations. These results contribute to our understanding of the relationship between psychopathic traits and the temporal dynamics of moral judgments, suggesting that (1) all participants, independent of their levels of psychopathic traits, have the same capacity to recognize moral information and process harmful experiences as indicated by early and late ERP components, respectively, and (2) the increased acceptability of harm- or fairness-related moral violations associated with higher psychopathic traits cannot be reliably captured by the ERP measure.