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Hi FSL experts,

I am trying to run a third-level analysis using the "Single-Group Average
with Additional Covariate" as explained on the FSL GLM wiki on my 4D COPE
image. My Design matrix looks like this:

[image: Inline image 1]

where EV1 is to represent the group mean activation and EV2 - EV8 are 7
covariates that I have already demeaned.

The contrast matrix looks like this:

[image: Inline image 2]

where I am to get brain areas that linearly correlate each behavioral
measure with BOLD activation.

Here is a copy of my randomise command:

randomise -i cope1_merged.nii.gz -o "covariates_" -d covariate2.mat -t
covariate2.con -m avg152T1_gray_thr_bin.nii.gz -n 5000 -T

The problem is that the resultant tfce_corrp images have so much
significance. Also, the range of the tstat images are huge (millions!). I
know something must not be right here. Also, i tried the other option of
not demeaning my data and then using "-D" option in randomise. This
resulted in values of 0.00 for every tfce_corrp image.

I would very much appreciate any help with this!

Thanks,

-Ricky