Brain correlates of adult attachment style: A voxel-based morphometry study.

Evidence from human and animal studies has shown that experiences of early attachment can influence brain development and structure. Adult attachment style develops from early attachment experiences. However, little is known about the relationship between gray matter volume and attachment style. Further, the structural bases of sex-related differences in adult attachment styles remain unknown. We used voxel-based morphometry to investigate the neuroanatomical basis underlying adult attachment styles and the structural basis of sex-related differences in adult attachment styles. Participants were 106 healthy young adults (57 women and 49 men; age, 20.8±1.55 years). Negative correlations were found between attachment avoidance and the volumes of the left middle temporal gyrus and the right parahippocampal gyrus, and between attachment anxiety and the right ventral anterior cingulate volume. Further analysis revealed that attachment avoidance was negatively correlated with the volume of the right middle occipital gyrus in women, but the inverse correlation was found in men. These findings suggest that differences in adult attachment styles are correlated with structural brain differences in adulthood, and that sex-related differences in adult attachment styles are associated with intrinsic structural brain differences involved in visual processing. These findings may improve our understanding of the pathophysiology of attachment-related disorder.