afni.nimh.nih.gov

Remove -corStr 'order : AR1', and try it again. In the output, interpret the results like this:

The F-stat for GROUP:FILL:TIME is for the interaction effect between GROUP and FILL over all the 6 TRs;
The F-stat for GROUP:TIME is for the main effect of GROUP over all the 6 TRs;
The F-stat for FILL:TIME is for the main effect of FILL over all the 6 TRs;
...

Gang