Jung-Lung Hsu et al., “Gender differences and age-related white matter changes of the human brain: a diffusion tensor imaging study,” Neuroimage 39, no. 2 (2008): 566–77; J. Sacher and J. Neumann et al., “Sexual dimorphism in the human brain: Evidence from neuroimaging,” Magnetic Resonance Imaging 3 (April 2013): 366–75, doi:10.1016 /j.mri.2012.06.007; H. Takeuchi and Y. Taki et al., “White Matter Structures Associated with Emotional Intelligence: Evidence from Diffusion Tensor Imaging,” Human Brain Mapping 5 (May 2013): 1025–34, doi:10.1002/hbm.21492.