Running head: FAMILIARITY AND AUDIENCE EFFECTS ON GIVING Familiarity and Audience Effects on Giving; an fMRI Study

Giving is often characterized by the conflicting decision to give up something of value to benefit others. Recent evidence indicated that giving is highly context dependent. To unravel the neural correlates of social context, in this study young adults (N = 32) performed a novel giving fMRI paradigm, in which they divided coins between self and known others (friends) or unknown (unfamiliar) others. A second manipulation included presence of others; giving decisions were made with an audience or anonymously. Results showed that participants gave more coins to a friend than to an unfamiliar other, and generally gave more in the presence of an audience. On a neural level, medial prefrontal cortex and the right insula were most active for relatively generous decisions. These findings possibly reflect that aversion of norm deviation or fairness concerns drive differences in the frequency of giving. Next, activation in separate sub regions of the TPJIPL (i.e., a region that comprises the temporo-parietal junction and inferior parietal lobule) was found for target and audience contexts. Overall, our findings suggest that donation size and social contextual information are processed in separable brain regions and that TPJ-IPL plays an important role in balancing selfand other-oriented motives related to the social context.