Gender Differences in the Structural Connectome of the Teenage Brain Revealed by Diffusion Tensor Imaging

The issue of biological differences between male and female brains is a controversial one with political positions or prior expectations having a seemingly strong influence on the interpretation of scientific data. The significance of this topic pertains to the gender differences in the prevalence of several psychiatric conditions, such as autism (much more common in males), attention deficit hyperactivity disorder (ADHD, much more common in males), Tourette's syndrome (much more common in males), schizophrenia (more common in males), dyslexia (more common in males), depression (more common in females), and eating disorders (much more common in females). Understanding how gender influences vulnerability to these conditions is of importance. Therefore, we aimed to investigate the gender differences in the brain structural network of teenagers using diffusion tensor imaging (DTI). There were 59 (33 males and 26 females) age- and education-matched subjects (age range, 13 to 14 years) enrolled in this study. The structural connectome was obtained on graph theoretical and network-based statistical (NBS) analyses. Our findings showed that teenage male brains are optimized for intra-hemispheric communication, while teenage female brains are optimized for inter-hemispheric communication. Our results also suggested that the network organization of teenage male brains is more local, more highly segregated, and closer to small-world networks than that of teenage female brains. This indicated that teenage male brains are structured to facilitate connectivity between perception and coordinated action, whereas teenage female brains are designed to facilitate communication between analytical and intuitive processing modes.