Gender Differences in Neural Mechanisms Underlying Moral Judgment of Disgust: A Functional MRI Study

Much recent research has sought to uncover the gender difference in neural mechanism of moral judgment; however, very few researches study the neural gender differences in a specific area of moral judgment. The aim of this functional magnetic resonance imaging (fMRI) study was to examine possible gender difference in neural response to (sexual) disgusting pictures versus neutral pictures. Seventeen participants (9 males) were scanned while viewing pictures of tactile intimacy in same-sex and being asked to evaluate whether the behaviors between the stimulus persons in the pictures were morally appropriate or not. Both the neural responses to pictures of tactile intimacy in same-sex between male participants and female participants and the neural response to pictures of male-male tactile intimacy and to pictures of female-female tactile intimacy were examined. The results showed that significantly increased differential activations to the disgusting pictures relative to the neutral pictures were observed in the dorsal medial prefrontal cortex (BA 9) and amygdala. Furthermore, greater activation to the pictures of female-female tactile intimacy was observed in the left superior frontal gyrus/dorsal medial prefrontal cortex (BA 6). These results suggested a possible neural gender difference between female’s immoral behavior and male’s immoral behavior.