Hi experts,
Currently, I am conducting an fMRI experiment. In my study, participants need to finish 2 tasks (e.g., A & B), each having 2 sessions, in the scanner. And for each run, there are three conditions (e.g., a, b & c). I want firstly to combine 2 sessions from each task (e.g., A1 & A2 to get combined-A and so as task B), and then combine 2 tasks to see contrasts across tasks.
I have read fsl userguide, it said "when running first-level registrations, turn off the Main structural image option and select the (brain-extracted) structural image as Standard space." My question is, does it matter to still use MNI152 as standard space in first-level? Because that was the way I did to register, and I compared my combined-A/B results from fsl with those from spm, basically, they were similar. However, I wonder if I keep using normal way to register images, will it bring any error in my subsequent analysis?
And after I combined each task, should I use cope*.feat to do further group analysis or use file ending with ".gfeat"?
Thanks for your concern and sorry for my disturbance.
Best wishes,
Shengjie
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