@article {NihonsugiENEURO.0226-21.2021, author = {Tsuyoshi Nihonsugi and Shotaro Numano and Masahiko Haruno}, title = {Functional connectivity basis and underlying cognitive mechanisms for gender differences in guilt aversion}, elocation-id = {ENEURO.0226-21.2021}, year = {2021}, doi = {10.1523/ENEURO.0226-21.2021}, publisher = {Society for Neuroscience}, abstract = {Prosocial behavior is pivotal to our society. Guilt aversion, which describes the tendency to reduce the discrepancy between a partner{\textquoteright}s expectation and his/her actual outcome, drives human prosocial behavior as does well-known inequity aversion. Although women are known to be more inequity averse than men, gender differences in guilt aversion remain unexplored. Here we conducted a functional magnetic resonance imaging (fMRI) study (n = 52) and a large-scale online behavioral study (n = 4723) of a trust game designed to investigate guilt and inequity aversions. The fMRI study demonstrated that men exhibited stronger guilt aversion and recruited right DLPFC-VMPFC connectivity more for guilt aversion than women, while VMPFC-DMPFC connectivity was commonly used in both genders. Furthermore, our regression analysis of the online behavioral data collected with Big Five and demographic factors replicated the gender differences and revealed that Big Five Conscientiousness (rule-based decision) correlated with guilt aversion only in men, but Agreeableness (empathetic consideration) correlated with guilt aversion in both genders. Thus, this study suggests that gender differences in prosocial behavior are heterogeneous depending on underlying motives in the brain and that the consideration of social norms plays a key role in the stronger guilt aversion in men.Significance StatementAlthough women are established to be more prosocial than men in terms of inequity aversion, gender differences in prosocial behavior based on motives prominent in guilt aversion are far less explored. Here we conducted a fMRI study and a large-scale online behavioral study to address gender differences in guilt aversion. We demonstrate that men are more sensitive to guilt aversion than women, and a prefrontal social-norm network is key to men{\textquoteright}s predominance in guilt-based prosocial behavior. These findings revealed the heterogeneity of gender differences in prosocial behavior depending on underlying motives and underlying neural mechanisms.}, URL = {https://www.eneuro.org/content/early/2021/11/23/ENEURO.0226-21.2021}, eprint = {https://www.eneuro.org/content/early/2021/11/23/ENEURO.0226-21.2021.full.pdf}, journal = {eNeuro} }