Hemispheric and Gender Related Differences in the Midcingulum Bundle: A DTI Study

The midcingulate cortex and therefore the underlying midcingulum bundle (MCB) as well play a major role in attention. Although a specific structure's function does strongly depend on its neuroanatomical characteristics, research assessing the morphological variability of the midcingulate region is rather sparse. The present study examined the micro- and macrostructure of the MCB in both hemispheres by means of diffusion-tensor imaging. Besides, effects of gender (Female = 40, Male = 39) and handedness (Lefthanders = 45, Righthanders = 34) were assessed as well. Measures of fractional anisotropy, mean diffusion, as well as the white matter volumes of the MCBs were assessed. By integration of multi-modal images, the MCB was isolated and confounding with callosal fibers was avoided. Evidence was found indicating differences between hemispheres and gender regarding both volume and microstructural characteristics of the MCB. Interestingly, gender-related effects seem to be substantially associated with variations in individual brain volumes. Handedness did not emerge as relevant factor in the analyses. These findings might indicate a higher functional connectivity of the left MCB and in males as compared to females. Hum Brain Mapp 30:383-391, 2009. (C) 2007 Wiley-Liss, Inc.