Hi all,
We've received feedback on a task-based fMRI paper asking us to summarize mean framewise displacement (FD) for each group, then include FD as a covariate in group-level analyses. Based on previous discussions in this forum, I am wondering if dvars is more suitable than mean FD?
In our original analyses, we used MCFLIRT for motion correction. To derive either FD or DVARS, I know I can use the fsl_motion_outliers command and I was hoping to perform this on already motion-corrected data (using the --nomoco option). From the wiki, it seems I may not be able to derive FD from already motion corrected data-- is this correct? Furthermore, is there a specific threshold I should be defining for DVARS using motion corrected files?
Finally, are there recommendations for summarizing FD or DVARS across runs and participants? When testing DVARS on an individual participant, I obtain an output of the confound file and the estimate file (which includes values for each time point in each run).
Thank you for any advice! It is much appreciated.
Best,
Erin
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