Sex differences in white matter development during adolescence: A DTI study

Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH, United States. Electronic address: .
Brain research (Impact Factor: 2.84). 08/2012; 1478:1-15. DOI: 10.1016/j.brainres.2012.08.038
Source: PubMed


Adolescence is a complex transitional period in human development, composing physical maturation, cognitive and social behavioral changes. The objective of this study is to investigate sex differences in white matter development and the associations between intelligence and white matter microstructure in the adolescent brain using diffusion tensor imaging (DTI) and tract-based spatial statistics (TBSS). In a cohort of 16 typically-developing adolescents aged 13 to 17 years, longitudinal DTI data were recorded from each subject at two time points that were one year apart. We used TBSS to analyze the diffusion indices including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). Our results suggest that boys (13-18 years) continued to demonstrate white matter maturation, whereas girls appeared to reach mature levels earlier. In addition, we identified significant positive correlations between FA and full-scale intelligence quotient (IQ) in the right inferior fronto-occipital fasciculus when both sexes were looked at together. Only girls showed significant positive correlations between FA and verbal IQ in the left cortico-spinal tract and superior longitudinal fasciculus. The preliminary evidence presented in this study supports that boys and girls have different developmental trajectories in white matter microstructure.

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    • "). Several research groups, for example, have found evidence of sex differences in the microstructure of neural white matter distributed throughout the adolescent brain (e.g., Herting et al., 2012; Wang et al., 2012 "
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    • "The positive FA correlation in women was associated with the observation that the splenium may be larger in females. A developmental study by Wang et al. (2012) used TBSS to study sex differences in the association between intelligence and white matter microstructure in the adolescent brain. Considering the whole sample, full-scale IQ was positively related to FA in the frontal part of the right inferior fronto-occipital fasciculus, which suggests that region specific increases in FA are associated with optimal cognitive performance. "
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May 21, 2014