Hi, Matthew The result for your command for tstat1 (fslstats tstat1.nii.gz -r -R) is: -4.514888 0.014184 -4.514888 2.628758 And I also did this for tstat2: -2.628758 1.928888 -2.628758 4.514888 both tfce_tstat1, tfce_corrp_tstat1, tfce_p_tstat1 and tfce_tstat2, tfce_corrp_tstat2, tfce_p_tstat2 are ALL blank images. And my randomise version is : Part of FSL (ID: 5.0.10) randomise v2.9 It is FSL 5.0.10 in a Mac OSX 10.11.6 I hope these informations could help. Thank you for your reply, Matthew !