afni.nimh.nih.gov

There are a couple of issues with your 3dMVM script:

1) The header for the subject column should be 'Subj', not 'subj.
2) You need to declare some of the variables as quantitative:

-qVars "Age,Edu,MMSE,ICV" \

3) Be aware of the centering issue: [afni.nimh.nih.gov]
4) Are you really interested in the interactions among those 4 quantitative variables?

Gang