Thanks for your reply. We start by averaging all 38 subject ROI masks into one composite mask:
3dMean -prefix allsubjectsmask.nii ~/Dropbox/fnirsauditoryproject2/processdata/p2process/S1001/viewer/Subject/1001_fullmask.nii
~/Dropbox/fnirsauditoryproject2/processdata/p2process/S1003/viewer/Subject/1003_fullmask.nii
~/Dropbox/fnirsauditoryproject2/processdata/p2process/S1004/viewer/Subject/1004_fullmask.nii
~/Dropbox/fnirsauditoryproject2/processdata/p2process/S1005/viewer/Subject/1005_fullmask.nii
~/Dropbox/fnirsauditoryproject2/processdata/p2process/S1006/viewer/Subject/1006_fullmask.nii
etc.
Then we threshold that mask to only include voxels in which all participants contributed data:
3dcalc -a allsubjectsmask.nii -expr 'equals(a,1)' -prefix allsubjectsmaskthresholded.nii
We ran 3dclustsim on this thresholded ROI mask to estimate minimum voxel cluster size (3dClustSim -mask allsubjectsmaskthresholded.nii -pthr 0.05).
