My question has to do with feeding lower level copes to higher level analyses. I have
checked through the archives and thought I found my answer, but I can't see how my
existing cope files allow me to do what I want to do.
At first level, each subject has multiple files that are fed into a second level:
Grp EV1 EV2
"A" "B"
Input 1 1 1 0
Input 2 1 1 0
Input 3 2 0 1
and 4 contrasts are formed:
EV1 EV2
A 1 0
-A -1 0
A-B 1 -1
B-A -1 1
I want to feed the mean A contrast and the A-B contrasts up to separate higher level
analyses. My assumption was that each of these contrasts should form a cope.feat file,
so if I want to group multiple subjects on the first contrast (mean of A), I select
cope1.feat files for the input at higher levels (and cope3.feat for the A-B contrast).
However, the above design only has 2 copes in its output (within each cope in the stats
subfolder, I do see cope1.nii.gz, cope2.nii.gz, etc), so it doesn't seem like I can feed each
of the 4 contrasts up to higher levels. Previous archive posts indicate that feat files (not
.nii.gz files) are to be fed into 2nd and higher levels.
Can you please offer some direction as to what I'm missing here?
Thanks,
Melissa
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