Gray matter density within the middle cingulate gyrus mediates the relationship between English proficiency and verbal creativity

English ability reflects a complex phenomenon predicted by many variables. It is often conceptualised as a combination of English proficiency, acquisition age, and immersed experience. Bilingualism is also associated with verbal creativity. However, there are few studies on the neural basis of the relationship between English proficiency and verbal creativity. We used voxel-based morphometry to assess the neuroanatomical basis underlying English proficiency in a large sample of college participants (N = 254). We identified a significant positive correlation between English proficiency and the middle cingulate gyrus, middle temporal gyrus, inferior frontal gyrus, cuneus, and the right inferior temporal gyrus. Mediation analysis revealed that the correlation between English proficiency and verbal creativity was mediated by the density region of the middle cingulate gyrus. These data suggested that left middle cingulate gyrus activation reflects cognitive flexibility and inhibition ability, which is linked to bilingualism, and improves bilinguals’ verbal creativity.