Dear FSL experts,
I have been using the randomise program to test for significant clusters of
activation that correlate with a behavioral variable, and have been using
the TFCE option to generate output maps.
If I understand the output correctly, the *tfce_corrp_tstat1.nii.gz is an
image that shows those clusters/voxels that have surpassed the corrections
applied from the permutation results in a 1-p format. I was wondering if
there was any way to determine a cluster-level p-value from these output
maps, similar to what is shown when using the cluster command (with the -p
option). I have assumed that masking the *_tstat1.nii.gz with the
*tfce_corrp_tstat1.nii.gz image and then running the cluster command would
be incorrect because it relies on assumptions from GRF theory??? Would the
proper way to extract a cluster level p be to determine the distribution of
clusters across all permutations, and then determine how many voxels are in
the cluster at the nth percentile? If so, is there a way to output this
information using the randomise command. If not, is there a way to compute
the cluster level p value?
Thanks in advance,
Eric
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