Fig. 2.

Axial views of significant between group differences showing fractional anisotropy (FA, in red), axial diffusivity (AD, in blue), and radial diffusivity (RD, in green) using Tract Based Spatial Statistics (TBSS). FA and AD overlap is shown in purple. FA and RD overlap is shown in yellow. An average T1 Montreal Neurological Institute (MNI) template was used to map between group differences. Note: Because it is difficult to see the regions of overlap on the original TBSS skeleton, the white matter tracts were thickened in this representation of the results (Smith et al., 2006). The group with familial risk for bipolar disorder shows increased FA, increased AD, and decreased RD compared with healthy controls. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)