Neural dynamics of unintentional empathy for physical and social pain.

Empathy for pain supports interpersonal interaction and underpins prosocial behavior. Yet the neural mechanisms of unintentional empathy for pain remain unclear, and it is unknown whether they differ by pain category. To characterize the temporal dynamics of two forms of unintentional pain empathy, we used a 1-back task to probe neural responses to physical versus social pain contexts. Event-related potential (ERP) analyses showed that unintentional empathy for physical pain was primarily reflected in the occipito-temporal N170, frontal-central P2, and parietal late positive potential (LPP). By contrast, unintentional empathy for social pain was mainly indexed by the frontal-central N400 and the parietal LPP. These findings indicate that unintentional empathy for physical pain emerges earlier and persists longer, consistent with a two-stage processing model, whereas unintentional empathy for social pain shows more pronounced differences only at later stages. Together, the results suggest that pain category significantly modulates unintentional empathy for pain.