Hi Qizhu, > What's the 'top report? Do you mean the > 'tbss_2_reg.oxxxx'' file? Inside this file, it > tells 20 iterations, target image size 182x218x182, etc. What Steve meant was for you to type the command "top" in a shell while running tbss_2. But as mentioned in his previous post, you just need to get the latest TBSS version, then it will run much faster as it will use our new in-house non-linear registration FNIRT. > BTW, I noticed that, at the end part of the FNIRT webpage, > there is a session called example usages introducing how to > register FA image to FMRIB58. Can I just follow that > instruction to complete the tbss_reg work? It would actually be better for you to update your FSL... Once you've done that, just re-run TBSS and it should go fastly and smoothly. Cheers, Gwenaelle