Abstract:  Cooperative behaviour is important for the sustainable development of human being. The underpinning mechanisms of the display and maintenance of this behaviour are, however, vastly unknown. These under-researched questions have attracted the attention of researchers in psychology, biology, economics, and neuroscience. In everyday life, cooperation is a complicated decision involving the cognitive perception of other peoples’ state of mind, emotion and behavioral intention during the interpersonal interaction. Cooperative behaviour happens in both individual and group levels. Besides motivated by economic reasons such as rewards and punishments, individuals may also cooperate because of social reasons, such as, trust and positive emotion. Social mindfulness means people notice and protect other’s autonomous needs in the process of interpersonal interactions. Social mindfulness is a crucial way to enhance other people’s positive emotion and establish interpersonal relationships. It provides a new perspective in the investigation of the dynamic processes underlying cooperative behaviour. Whether individuals will contribute more to the group depends on their experiencing of positive emotion in interpersonal interaction. The present research aims to investigate this process through two game experiments conducted in real contexts of interpersonal interaction. This research revealed how and why the people’s social mindfulness would influence recipient’s cooperative behaviour through positive emotion. Experiment 1 was in a between-subject design with people’s social mindfulness manipulated in a “selection of goods” game and the recipient’s positive emotion assessed after the game. The recipients participated in a public goods game and the amount of contribution served as an indicator of their cooperative behaviour. The results showed that recipients experiencing high social mindfulness in the “selection of goods” game reported more positive emotion and less negative emotion. More importantly, they were willing to contribute more resources in their subsequent public goods game. Positive emotion mediated the relation between perceived social mindfulness and cooperative behaviour. Based on the results in Experiment 1, we further examined the role of autonomous needs in the relation of social mindfulness and positive emotion in Experiment 2. In this experiment, the level of autonomous needs were manipulated by asking participants to select the amount of help they would like their opponents to give card selection game. The results showed that positive emotion mediated the relation between perceived social mindfulness and cooperative behaviour. Moreover, autonomous needs moderated the link of perceived social mindfulness and positive emotion. Specifically, as compared to those with low autonomous needs, recipients with high autonomous needs experienced less positive emotion when their needs were not satisfied. In conclusion, the present research demonstrates that positive emotion is an important mechanism which helps convey people’s social mindfulness and results in recipient’s cooperative behaviour. The satisfaction of autonomous needs is the basic reason obtaining positive emotion experience. These findings expanded the research on cooperative behaviour and provide evidence on the development of social mindfulness. The present findings shed light on daily decision and management on issues such as: (1) selecting right time to express social mindfulness; (2) enhancing employees’ well-being through social mindfulness; and (3) training employees’ social mindfulness and the helping them establish an “other people oriented” cognitive style.

Key words: cooperative behaviour, social mindfulness, positive emotion, need for autonomy, public good game