Cooperation is an essential behavior in constructing and maintaining human societies and the past two decades of cognitive neuroscience and behavioral economics experiments have improved our understanding of neurophysiological bases of such behavior. Neuroimaging suggests that cooperation is associated with reward-processing brain areas including rostral anterior cingulate cortex (rACC)1, which is known to modulate fear processing in amygdala2; as well as the ventromedial prefrontal cortex (vmPFC), nucleus accumbens (NACC), and caudate3,4,5. Recent research gives us an even more granular view of the pathways involved, showing that “pay-it-forward” indirect reciprocity (altruism without expectation of returned favor, which underlies large-scale cooperation, specifically based on empathy and other-regarding social preferences rather than reputation) is associated with activation of the anterior insula (AI), which in turn regulates the caudate6.

Cooperation can be generally defined as individual behavior whereby “one individual pays a cost for others to receive a benefit”7. Cooperation can be further modelled as equilibrium of games where subjects still act in their self-interest but their utility function (a function that defines individual preferences of given scenarios) includes social preferences that have been modelled in various ways, such as inequity aversion, a second utility function over others’ well-being, etc8,9,10. In the present study we focus on the act of making a private decision regarding what proportion of payment to keep for oneself and what proportion to make as a charitable donation, which is a form of indirect reciprocity or generalized altruism.

Evidence also suggests that certain types of social environments, social cues and stimuli can alter the people’s perception on social dilemma (i.e. individual cost vs. collective benefit) and can enhance human cooperation. For example, people are more cooperative when they connect with cooperative individuals than when they connect with non-cooperative individuals11. Providing reputation information of others (how cooperative they are in the past) can contribute to constructing a cooperative social norm in social networks12,13. It is also known that a time pressure (study participants are asked to decide cooperate or defect within certain seconds in economic games) can improve the level of cooperation14. Another study found that the introduction of integrative institutions activates altruism and improves cooperation among deeply divided ethnoreligious groups15. A series of studies found that an exposure to oxytocin through nasal intake improved the level of cooperation16,17.

Meditation is “a form of mental training that aims to improve an individual’s core psychological capacities, such as attentional and emotional self-regulation”18, which has gained popularity as a focus of research over the past decade19. Meditation has a wide range of types such as loving kindness meditation (taught by spiritual leaders or experts versed in the Buddhist tradition, focused on silent repetition of phrases based on Buddhist teachings, and incorporated into holistic health and group support programs) and mindfulness meditation (increasingly taught by trained clinical psychologists, focused on emotional self-regulation and focusing attention, and incorporated into cognitive therapy and clinical care). Meditation both over short-term and long-term has been found to improve cognition20,21,22. One study of 54 college students in Singapore playing the Dictator Game (where the Dictator, player A, divides money provided by the experimenter between what she wants to keep for herself and what she wants to give away to an anonymous player B) reported that loving kindness meditation led to higher cooperation23.

Mindfulness meditation emphasizes non-judgmental attention to experiences in the present moment24. Meditation practices mainly modulate brain activities responsible for cognitive control, emotion regulation, and empathy, each of which is associated with specific brain areas including the anterior cingulate cortex (ACC), insula, and amygdala25,26,27,28.

A recent meta-analysis of clinical data concludes that mindfulness meditation practices have a positive effect on anxiety, depression, stress, and pain regulation18,25,29,30,31,32,33. However, the role of mindfulness meditation in cooperation has not been well investigated. Therefore, in the present study we explored the effect of mindfulness meditation on charitable giving as a real-world manifestation of human altruism relevant to large scale social cooperation.

Study participants recruited online were assigned randomly to treatment or control. In the treatment condition, participants watched a short mindfulness meditation video and were given an option to donate any part of their participation payment to a charity, whereas in the control condition, participants watched a drawing instruction video instead. Given a charity organization has little chance to directly, financially benefit our study participants, this type of giving measures a general form of altruism and is similar to that of cooperation in Dictator Game.