Brain structure links trait hostile attribution bias and attitudes toward violence.

The majority of research regarding hostile attribution bias focuses on its effect on aggression. However, little is known about the brain structure associated with trait hostile attribution bias and the mediating mechanism underlying this link. The current study uses voxel-based morphometry (VBM) to identify the brain regions related to individual differences in trait hostile attribution bias, measured by a Word Sentence Association Paradigm - Hostility in a sample of 176 undergraduate students. Subsequently, two mediation models with regard to brain structure, trait hostile attribution bias, and attitudes toward violence (measured by the Attitudes toward Violence Scale) were analyzed. The results reveal that trait hostile attribution bias is positively correlated with gray matter volume (GMV) in the left orbitofrontal cortex (OFC) and negatively associated with the left lingual gyrus (LG). Furthermore, attitudes toward violence acted as a mediator underlying the association between the left OFC volume and trait hostile attribution bias. Such bias also mediated the relationship between the left OFC and attitudes toward violence. We argue that attitudes toward violence and trait hostile attribution bias seem to predict each other, and the GMV in the left OFC may involve the underlying cognitive mechanism of the bidirectional relationship between the two variables. These results and ideas may shed light on the current understanding of the relationships of the brain's anatomical features, attitudes toward violence, and trait hostile attribution bias.