Reading Intention Where There Is None: Neurobehavioral Correlates of Intention Attribution of Morally Ambiguous Scenarios in Borderline Personality Disorder.

BACKGROUND: Borderline personality disorder (BPD) is characterized by altered social cognition, including a tendency to bias intention attribution in ambiguous situations. However, the neurobehavioral mechanisms underlying this tendency remain poorly understood. Here, we examined whether intention attribution is disturbed in BPD and reflected in behavioral bias and altered neural processing of morally ambiguous social information.

METHODS: A total of 71 individuals with BPD (55 female, 16 male) and 72 healthy controls (56 female, 16 male) were included. Participants viewed harm-based scenarios depicting intentional and accidental actions while electroencephalography was recorded. Behavioral responses and event-related potentials were analyzed exploratorily to examine group differences in intention attribution and neural differentiation.

RESULTS: Behaviorally, individuals with BPD were more likely to misinterpret accidental harm as intentional, whereas responses to intentional harms did not differ between groups. Mass-univariate event-related potential analyses revealed group differences in early frontocentral (approximately 200-250 ms) and later centroparietal (734-789 ms) time windows. Healthy controls showed greater accidental-intentional differentiation in the early windows, whereas individuals with BPD exhibited reduced neural differentiation. In contrast, the later effect showed greater differentiation in the BPD group.

CONCLUSIONS: These condition-specific findings indicate a selective intention-attribution bias in BPD alongside altered neural differentiation of ambiguous social information at earlier and later time points. More broadly, social judgment disturbances in BPD may be particularly evident when harmful outcomes conflict with innocent intentions, rather than reflecting generalized response differences.