The Serial Effects of Callous-Unemotional Traits and Gray Matter Density in the Right Dorsomedial Prefrontal Cortex on Social Desirability.

Social desirability affects several aspects of human life. However, the neuropsychological mechanisms underlying individual differences in social desirability remain unclear. This study explored the neuroanatomical basis of individual differences in social desirability using regional gray matter density (rGMD) as a brain indicator in a sample of 158 Chinese college students (79 males; M_age = 21.42, SD = 1.96). Next, we tested the serial effects of callous-unemotional traits (a personality inhibitor of social desirability) and the uncovered brain structural correlation on individual differences in social desirability. Our results indicated that rGMD in the right dorsomedial prefrontal cortex (dmPFC) is associated with individual differences in social desirability. Additionally, callous-unemotional traits were negatively associated with individual differences in social desirability through lower rGMD in the right dmPFC. This study provides the serial effects of personality inhibitor and neural correlate on individual differences in social desirability, which facilitates a more complete understanding of social desirability from the perspective of inhibition, and suggests a neuropsychological mechanism underlying lower-order personality traits.