Dear all,
I have some question:
1. in first-level analysis, when I run fmri model specification and after that model estimation, a mask.nii image is made, I want to know how is the mask image made?
2.i have a problem in extracting WM time series:
when I extracted time series with the procedure is in spm manual, for some subject, the mask image didn't include the coordinate of center and radius that I considered for the WM region, but maybe the functional image include this region, How do you think this will be resolved and why?
3. another procedure that I tested for extracting time series was using mask image of WM and CSF from segmentation part, and calculated first principle eigenvariate of all signals in these masks as time series of WM, but in the figure that SPM show after extracting time series, the region showed, for example as WM, seems it isn't WM! what do you think about this?
4. if I want to calculate the mean of the signals instead of first principle eigenvariate of all signals in masks in part 3 as time series of WM, how can I do this?
Many thanks,
s.sh
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