Dear SPMers,
I am a beginner on fMRI and I'm confused on the Model Specification step. It would be
great if you could help me!
I have an event-related design, and I'd like to set "scans" as the onset units.
1) Am I right that all the onsets indexes have to be reduced by one, so if the event comes
together with the first pulse, it has the onset=0, with the 5th pulse - onset=4, and so on?
2)I removed the first 5 volumes of my session, since I didn't want them to be processed
with others. So I only want to use the volumes from XXXX_006.nii to XXXX_400.nii for
my model. What if I still have the events corresponding to the pulses 1:5 in my onsets
vector? Do I need to remove these events? Do I need to change the numbering of all
events so that onset "0" corresponds to the 6th pulse?
Thanks a lot!
Sincerely,
Irina
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