Hi,
I might be off base, but is it correct to assume that the "pre-threshold masking" + "voxel level thresholding" options in FEAT is equivalent to the small volume correction in SPM?
Also, how are the "number_of_resels" computed for this approach? I'm not 100% sure where it is pulling the value it used in the -g option for ptoz in the feat logs:
/usr/local/fsl/bin/fslmaths thresh_zstat4 -mas /path/to/the/prethreshold/mask.nii.gz thresh_zstat4
echo 333 > thresh_zstat4.vol
zstat4: DLH=0.81907 VOLUME=333 RESELS=5.64651
/usr/local/fsl/bin/ptoz 0.05 -g 58
3.887894
I thought the ptoz command would use the number of resels reported in the "stats/smoothness" file. Or is that the size of each resel, making the number_of_resels = VOLUME/RESELS ??
Thanks!
David
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