Dear Janek,
Default (internal) 2nd level mask is usually a common space between all
input files (1st level masks). It means that even one "imperfect"
subject mask will reduce the tested space in whole group. I would
suggest to check reg all 1st level masks and browse them to see if all
of your subjects were normalized to MNI correctly. Sometimes it's the
matter of one black sheep...
Best,
Jacek
W dniu 3/15/2018 o 10:22 PM, Jan Stasiński pisze:
> Dear SPMers,
> please help me, I am working on 2nd level fMRI data analysis. I have
> my functional data normalized to MNI space together with structural data.
> At 1st level, my contrast images (later used at 2nd level) are
> normalized to MNI and they make sense but at the 2nd level (simple
> one-sample t-test) my contrast image seems to be no longer normalized
> and when viewed overlayed on the average brain or over single_subT1
> sections it does not fit and seems much smaller. Why is that?
> Is there any way to fix this?
>
> I would be grateful for your help
> Janek
> Boston University
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