Isolated clefts of the lip and/or palate (ICLP) are developmental craniofacial abnormalities that have consistently been linked to increased social inhibition or shyness. Two explanations have been proposed: 1) psychosocial factors related to differences in facial appearance may lead to low selfconcept and subsequent shyness, or 2) abnormal development of brain structures involved in social function, such as the ventral frontal cortex (VFC), may underlie the difference. To investigate these two possibilities this study was designed to evaluate measures of social function in relation to measures of self-concept and VFC morphology. Subjects included 30 boys (age 7-12) with ICLP and a comparison group of 43 boys without cleft in the same age category. Social function and selfconcept were assessed using questionnaires with standardized scoring filled out by subjects and one of their parents. The cortical volume and surface area of the VFC, composed of the orbitofrontal cortex (OFC) and straight gyrus (SG), were evaluated using structural magnetic resonance imaging. The ICLP subjects had significantly impaired social function relative to the comparison group. No difference in self-concept was identified. VFC morphology revealed significant differences between groups, particularly decreased volume and surface area in the left SG of the ICLP group. Moreover, abnormal VFC measures were correlated with social dysfunction but measures of self-concept were

The ventral frontal cortex (VFC) has been shown to differ morphologically between sexes. Social cognition, which many studies demonstrate involves the VFC, also differs between sexes, with females being more adept than males. In a previous study of subregions of the VFC in our lab, in an adult population, size of the straight gyrus (SG) but not the orbitofrontal cortex (OFC), differed between sexes and correlated with better performance on a test of social cognition and with greater identification with feminine characteristics. To investigate the relationship between VFC structure and social cognition in children, VFC gray matter volumes were measured on MRIs from 37 boys and 37 girls aged 7 to 17. The VFC was subdivided into the OFC and SG. Subjects were also administered a test of social perceptiveness and a rating scale of femininity/masculinity. In contrast to our findings in adults, the SG was slightly smaller in girls than boys. In girls, but not boys, smaller SG volumes significantly correlated with better social perception and higher identification with feminine traits. No volume differences by sex or significant correlations were found with the OFC. These data suggest a complex relationship between femininity, social cognition and SG morphology.