关键词: 加工模式, 亲社会行为, 紧急性, 社会启发式假说, 事件相关电位

Abstract: Prosocial behavior is suggested to be a central feature of human life and there is an ongoing debate whether individuals have, therefore, developed a general intuitive tendency to act prosocially or not. Although previous studies have found various indicators of intuitive prosociality from different perspectives, evidence on the potential causal relationship between processing mods and prosocial behavior is mixed. The social heuristics hypothesis (SHH) has therefore been proposed as a theoretical framework to addressing conflicting evidence. The SHH posits that associations between processing mode and prosocial behavior are complex and multifaceted, prone to shifting according to individual variability and the contexts in which it occurs. A previous study has revealed that intuitive prosocial behavior would be likely to emerge when a perceived emergency requires immediate response. We expect that processing mode (intuition vs. deliberation) will impact people’s decision-making in different helping situations. The study focused on charitable giving. Using event-related potentials (ERPs), we examine the neural mechanism of the effect of processing mode and emergency on helping behaviors, and explored whether a neural signature that rapidly encodes the motivational salience of an event, the P3, can regulate by processing mode × situation interaction. Participants allocated varying amounts of money between themselves and charities they initially labelled as emergency or non-emergency situation that promoted intuitive or deliberative decision making. Each participant was presented with a 70-yuan bill. An instruction screen explained that the task required participants to “Accept” or “Reject” donation offers affecting their 70-yuan. To manipulate processing mode, each participant completed fast donation sessions that instructed them to make their decision as fast as possible, and slow donation sessions that instructed them must stop and reflect for at least 5 seconds before deciding. EEG signals were recorded during decision making. The behavioral results indicated that both average contributions and average acceptance rates were affected by emergency, with emergency events eliciting more helping behavior compared to non-emergency events. Moreover, participants considered the offer costliness when decision making. In the case of emergency situations, participants were more likely to accept high-cost offers than in the non-emergency situations. The ERP results showed that: a) In the early stages, intuitive processing induced a more negative anterior N1 (AN1) compared to deliberative processing. b) Deliberative processing was associated with a more positive P2 compared to intuitive processing. c) In non-emergency situations, deliberative processing induced a more positive P3 compared to intuitive processing, whereas no significant differences were observed between processing mode in emergency situations. These results suggest that prosocial behavior is affected by both the emergency of event and offer costliness. As costs increase, individuals are more inclined to help in emergency situations than in non-emergency situations. Furthermore, processing mode affects individual’s early attention and the evaluation of stimuli. Stimuli in intuition condition can capture more early attention, while stimuli in deliberation condition can get sufficient processing. Notably, deliberative processing of non-emergency events involves greater decision-making conflicts and consumes more psychological resources. Overall, these findings shed light on the connection between processing mode and human prosociality, and extend our understanding of the social heuristics hypothesis.

Key words: processing mode, prosocial behavior, emergency, the social heuristics hypothesis, event-related potential (ERP)