Proposer's moral identity modulates fairness processing in the ultimatum game: Evidence from behavior and brain potentials.

Economic decision-making is pivotal to both human private interests and the national economy. People pursue fairness in economic decision-making, but a proposer's moral identity can influence fairness processing. Previous ERP studies have revealed that moral identity has an effect on fairness considerations in the Ultimatum Game (UG), but the findings are inconsistent. To address the issue, we revised the moral-related sentences and used the ERP technique to measure the corresponding neural mechanism. We have observed that the fairness effect in UG can be mirrored in both MFN and P300 changes, whereas the moral identity effect on fairness in UG can be reflected by MFN but not P300 changes. These findings indicate that the moral identity of the proposer can modulate fairness processing in UG. The current study opens new avenues for clarifying the temporal course of the relationship between the proposer's moral identity and fairness in economic decision-making, which is beneficial for understanding the influencing mechanism of fairness processing and fair allocations in complex social contexts.

Construction and validation of the Dalian emotional movement open-source set (DEMOS).

Human body movements are important for emotion recognition and social communication and have received extensive attention from researchers. In this field, emotional biological motion stimuli, as depicted by point-light displays, are widely used. However, the number of stimuli in the existing material library is small, and there is a lack of standardized indicators, which subsequently limits experimental design and conduction. Therefore, based on our prior kinematic dataset, we constructed the Dalian Emotional Movement Open-source Set (DEMOS) using computational modeling. The DEMOS has three views (i.e., frontal 0°, left 45°, and left 90°) and in total comprises 2664 high-quality videos of emotional biological motion, each displaying happiness, sadness, anger, fear, disgust, and neutral. All stimuli were validated in terms of recognition accuracy, emotional intensity, and subjective movement. The objective movement for each expression was also calculated. The DEMOS can be downloaded for free from https://osf.io/83fst/ . To our knowledge, this is the largest multi-view emotional biological motion set based on the whole body. The DEMOS can be applied in many fields, including affective computing, social cognition, and psychiatry.

Context-based interpersonal relationship modulates social comparison between outcomes: an event-related potential study.

Social comparison is a common behavior that largely determines people's experience of decision outcome. Previous research has showed that interpersonal relationship plays a pivotal role in social comparison. In the current study, we investigated whether the manipulation of context-based relationship would affect participants' comparison of self-outcome and other-outcome. Participants first finished a trust game with likeable (dislikeable) partner and then they were involved in a gambling task and observed the outcomes for themselves and for partners. According to self-reports, participants were more satisfied with likeable partner's gains than losses only when they received gains, but they were always more satisfied with dislikeable player's losses compared to gains. Event-related potentials including the feedback-related negativity (FRN), P3 and late positive component (LPC) were sensitive to context-based relationship. Specifically, the prediction error signal (indexed by the FRN) was largest when participants received losses but dislikeable player received gains. Meanwhile, the P3 indicates that participants had stronger motivation to outperform dislikeable player. Finally, the LPC was larger when participants received the same outcomes with dislikeable players. In general, our results support the key point of the self-evaluation maintenance model that personal closeness modulates subjective sensitivity when drawing a comparison of one's outcomes with other's outcomes.