Dear Saad, Thank you for the script which so far seems to have worked fine. A quick question - when running randomise should one use the mfibresmask.nii.gz file rather than the mean_FA_skeleton_mask.nii.gz (as generated by a standard FA TBSS analysis) and if so why ? I notice there is a difference between them with the former being seemingly more conservative. Thanks. V _________________________________________________________________ http://clk.atdmt.com/UKM/go/197222280/direct/01/ Do you have a story that started on Hotmail? Tell us now