Posted by Annapaola Prestia Laboratory of Epidemiology Neuroimaging and Telemedicine, IRCCS Centro San Giovanni di Dio FBF, The National Centre for Research and Care of Alzheimer’s and Mental Diseases, Brescia, Italy. April 2011

The human brain is asymmetric in terms of structure and function and some aspects of these brain asymmetries also interact with gender. Despite the advances in brain asymmetry research, however, little is known about whether there are differences in the topological organization of brain networks between the hemispheres and whether those differences are related to gender. In this recent study the resting-state functional MRI (R-fMRI) was utilized to investigate hemisphere- and gender-related differences in the organizational patterns of functional networks in the human brain. To address these issues, R-fMRI data of 86 young, healthy, right-handed adults (38 males and 48 females) were acquired, and the brain was parcellated into 90 cortical and subcortical regions. Researchers observed that males and females have quite different asymmetric patterns in their network local efficiencies and suggest that these differences are closely related to the behavioral differences: males tended to be more locally efficient in their right hemispheric networks, but females tended to be more locally efficient in their left hemispheric networks. Significant hemisphere-related differences in the regional nodal characteristics were observed in various brain regions, such as the frontal and occipital regions (leftward asymmetry) and the temporal regions (rightward asymmetry). Most regions that exhibited significant hemisphere-related differences in the present study have formerly been observed to be structurally or functionally asymmetric. The results indicate that a complex brain network analysis could be a profitable tool for investigating individual differences in brain function.

April 18, 2011