I used randomize with 10000 iterations to do a one sample t test. I was surprised to find MORE areas of activation than FLAME1+2. Oddly, the additional areas of activation were basically a halo in the front of the brain and a lot of activation in the ventricles. This is basically what one would expect from movement artifacts if R Kelly is correct.
In my other contrast, I found basically the same activation pattern as FLAME1+2 gave me with slightly smaller clusters.
You can see the image here: http://killough-walden.com/eric/screenshot.png Red-Yellow is randomize while Blue is FLAME1+2.
My question is: Are permutation tests somehow particularly susceptible to motion artifacts? Or, more importantly, are permutation tests susceptible to motion artifacts under certain conditions?
The commands I used were:
randomise -i filtered_func_data.nii.gz -o OneSampTCope110000 -1 -v 5 -T -n 10000
fslview OneSampTCope110000_tfce_corrp_tstat1.nii.gz
I thresholded at .95 in FSLVIEW.
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