Sex differences in anatomic measures of interhemispheric connectivity: correlations with cognition in women but not men

A robust sex difference in the splenium of the corpus callosum, reflectinggreater interhemispheric connectivity in women, was observed on magneticresonance images from 114 individuals. In addition, bulbosity of the corpuscallosum correlated with better cognitive performance in women but not inmen, indicating that the degree of interhemispheric connectivity hasdifferent implications for men and women. These findings were based on anew image analysis technique which allows investigation of localvariability in brain morphology.