I'm doing a volumetric group analysis of DTI data and am now stuck. I ran mri_preproc, mri_info, and mri_glmfit to create sig.mgh. I run the following command and load sig.mgh as an overlay:

tkmedit fsaverage brainmask.mgz lh.white -aux T1.mgz -aux-surface rh.white

I'm wondering if this is the correct usage for the sig.mgh file, and if someone could point me in the right direction for what steps are next? Thank you.

   -Ryan