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Human altruism has a unique feature among animals. It goes beyond genetically unrelated individuals and shows huge heterogeneity among individuals. In my previous study, I demonstrated that the grey matter volume in TPJ reflects the inter-individual variation of altruism. However, structural differences do not tell when and how altruistic acts are taken. In addition, altruistic acts are driven by various motivations, such as empathy, reciprocity and social norms. I therefore investigated neural mechanisms underlying context-independent and -dependent altruistic decision making processes. Firstly, I have examined brain regions involved in altruistic acts, independent of contexts. I found that the anterior insular cortex and inferior parietal cortex including TPJ are active when altruistic action is taken. Secondly, depending on the decision contexts, other brain areas are also recruited when altruistic acts are taken. Connectivity analysis has revealed that the anterior insular cortex drives the inferior parietal cortex and the context-dependent areas. The results suggest that the anterior insular cortex serves as the centre of altruistic behaviour by orchestrating context-independent and -dependent brain areas. Lastly, I will discuss the current problems in human cognitive neuroscience and future perspectives to address causality in neural mechanism of cognition.