The neural mechanisms of identifiable victim effect in prosocial decision-making.

The phenomenon known as the "identifiable victim effect" describes how individuals tend to offer more assistance to victims they can identify with than to those who are vague or abstract. The neural underpinnings of this effect, however, remain elusive. Our study utilized functional magnetic resonance imaging to delve into how the "identifiable victim effect" influences prosocial decision-making, considering different types of helping costs, across two distinct tasks. Participants were instructed to decide whether to help a victim with personal information shown (i.e., the identifiable victim) and an unidentifiable one by costing their money (task 1) or physical effort (task 2). Behaviorally, we observed a pronounced preference in both tasks for aiding identifiable victims over anonymous ones, highlighting a robust "identifiable victim effect." On a neural level, this effect was associated with heightened activity in brain areas like the bilateral temporoparietal junction (TPJ) when participants confronted anonymous victims, potentially indicating a more intensive mentalizing process for less concrete victims. Additionally, we noted that the TPJ's influence on value judgment processes is mediated through its functional connectivity with the medial prefrontal cortex. These insights contribute significantly to our understanding of the psychological and neural dynamics underlying the identifiable victim effect.

Three stages of perceiving consecutively moral behaviors: Neurophysiological effect of agent and valence on the moral judgments.

The present study investigates how agents and the moral valence of the acts affect moral judgments when two consecutively behaviors are perceived, with each describing morally salient behaviors done by the same or different agent(s). Participants had to rate the likableness/pleasantness of the agents/behaviors. Behavioral results indicated that rating the likableness of the agent was mainly depended on the morally diagnostic character of the agent while rating the pleasantness of the behaviors was mainly depended on the moral valence of the behaviors per se. ERP results showed: 1) larger N1 was found in response to the agent consistently acting immorally, indicating an early detection of social threatening information. 2) Compared with agents who consistently act morally which provided no norm- or expectation-violation information, other conditions induced larger N400, indicating greater cognitive effort was recruited when the present moral information violated the participants' prior knowledge to the agent. 3) Increased LPP was found in response to the agent consistently acting morally (vs. moral behaviors acted by different agents), representing that people may allocate more attention to positive information during this stage. We suggest that this three-stage scheme is a common model when people encounter consecutive moral events.