Dear Torben, dear Cyril,
> It is difficult to say in general anything about this. If for instance
> there is no motion at all, then the mask defined by the effects of
> interest will be very similar in the two cases. In other cases the
> difference can be huge.
chiming in on this, I have also played with the piece of code Torben so
kindly provided and tested it in two simple single-session analyses.
There was almost no motion in the first session and quite a bit in the
second one.
In both cases, the p-values were identical in both scenarios
(subtracting spmT[new way] from spmT[old way] is pretty much an empty
image). However, if one checks the effects of interest, the difference
in these spmF-images is rather striking and convincing, removing some
obvious ring artefacts from the effects of interest. So it does do
something.
Now, I know I am naive about this, but in how far does this help me if I
take my (unchanged) con-images to the second level? Any advice is
appreciated!
Best,
Marko
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Marko Wilke (Dr.med./M.D.)
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Universitäts-Kinderklinik University Children's Hospital
Abt. III (Neuropädiatrie) Dept. III (Pediatric neurology)
Hoppe-Seyler-Str. 1, D - 72076 Tübingen
Tel.: (+49) 07071 29-83416 Fax: (+49) 07071 29-5473
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