Sex differences in thickness, and folding developments throughout the cortex

Abstract

While significant differences in male and female brain structures have commonly been reported, only a few studies have focused on the sex differences in the way the cortex matures over time. Here, we investigated cortical thickness maturation between the age of 6 to 30 years, using 209 longitudinally-acquired brain MRI scans. Significant sex differences in the trajectories of cortical thickness change with age were evidenced using non-linear mixed effects models. Similar statistical analyses were computed to quantify the differences between cortical gyrification changes with age in males and females. During adolescence, we observed a statistically significant higher rate of cortical thinning in females compared to males in the right temporal regions, the left temporoparietal junction and the left orbitofrontal cortex. This finding is interpreted as a faster maturation of the social brain areas in females. Concomitantly, statistically significant sex differences in cortical folding changes with age were observed only in one cluster of the right prefrontal regions, suggesting that the mechanisms underlying cortical thickness and gyrification changes with age are quite distinct. Sexual dimorphism in the developmental course of the cortical maturation may be associated with the different age of onset and clinical presentation of many psychiatric disorders between males and females.

Reduced brain cortical folding in schizophrenia revealed in two independent samples

“…healthy children, adolescents and young adults, Mutlu et al (2013) found a linearly decreasing lGI with age in most cortical regions, with the exception of the medial prefrontal and cuneus/precuneus regions where lGI did not correlate with age. As such, the localization of our two clusters with decreased lGI with age and the cluster without significant age-related decrease is largely in agreement with the topological distribution of the trajectories reported by Mutlu et al The absence of significant age × diagnosis interaction effect in the present study suggests that group differences in lGI are independent of age.…”

Problematic internet use is associated with structural alterations in the brain reward system in females

“…However, Possible gender related associations between brain morphology and Internet habits should be further investigated as sexual dimorphism in the brain structure can contribute to behavioural differences (Mutlu et al 2013;Sun et al 2015). Longitudinal studies are highly needed to test whether these structural correlates are the result of overall additive tendencies or specific to maladaptive Internet use.…”

Grey matter correlates of autistic traits in women with anorexia nervosa

“…54 Also, cortical TPJ thinning during adolescence is localized to the left hemisphere. 35 Nevertheless, we observed bilateral STS grey matter reductions in women with anorexia nervosa and found trends toward associations between TPJ grey matter volume and autistic traits bilaterally. Any lateralization should therefore be interpreted with caution, and further studies in larger samples are required to confirm such effects.…”

“…52 Notably, healthy girls exhibit a higher rate of cortical thinning of social brain regions during adolescence than boys, including thinning of the right temporal cortex and the left TPJ. 35 Our findings raise the possibility that adolescent onset of anorexia nervosa may be linked to such cortical developments. However, further studies directly comparing boys and girls with anorexia nervosa are required to characterize shared and distinct alterations; this is a particularly difficult challenge given the low prevalence of anorexia nervosa in boys.…”

“…Because brain regions linked to social cognition, including temporal cortex areas such as the TPJ, mature during adolescence, 35 we included age as a covariate. The results were assessed using nonparametric permutation testing clusterwise inference as implemented in the Statistical NonParametric Mapping toolbox (http://warwick.ac.uk/snpm), with a cluster-forming threshold of 0.005 and a family-wise error (FWE) of 0.05.…”