Andrew L. Alexander1, Jee Eun Lee1, Erin D. Bigler2, Molly B. DuBray2, Alyson Froehlich2, Nicholas Lange3, Thomas P. Fletcher2, Moo K. Chung1, Janet E. Lainhart2
1University of Wisconsin, Madison, WI, USA; 2University of Utah, Salt Lake City, UT, USA; 3Laboratory for Statistical Neuroimaging McLean Hospital, Belmont, MA, USA
DTI measures were compared between a group of children and young adults with autism versus typically developing controls. Two advanced voxel-based analysis methods T-SPOON and TBSS were used for the group comparison study. Spatially diffuse WM differences were observed for FA, mean diffusivity and the third (smallest) eigenvalue, but not the first (largest) eigenvalue. In general, the T-SPOON voxel-based analysis appeared to be more sensitive to group differences than TBSS although both methods found extensive group differences. The specific biological mechanism of the differences in the DTI measures is still unknown; however, they are consistent with recent theories of brain underconnectivity in autism.