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Dear experts,

I have performed PALM analysis on CIFTI files (myelin maps from HCP). I
used tail approximation and 500 permutations. I did it with the -logp
option so that when I visualise the results I set the threshhold with the
minimum at 1.3 (which corresponds to 0.05) and max to whatever max there is
in the picture. Now my results seem a bit peculiar and I wanted to ask your
advice.

I have six contrasts (g1>g2, g2>g1 and positive and negative effects of age
and gender). In g1>g2 contrast literally almost whole brain is significant,
whereas in the g2>g1 I cannot even threshhold anything because everything
is zero. The positive effect of age, however, is also significant almost
everywhere.
Now I am a bit confused, a) if the positive effect of age is significant in
almost all regions, should the g1>g2 comparison be not as strong (because
it should be adjusted for the age effect?) Is it normal that g1>g2 still
shows so much significance everywhere (same regions as the positive age
effect)? and b) Even though it is line with my expectations I am a bit wary
to see significant differences covering the whole brain. Is there maybe
some error that might have led to that or something I have to double check?
So far I checked my GLM and input files and cannot find anything
weird/wrong there.

Sorry for the probably basic question and thanks a lot for the help!

Lisa