afni.nimh.nih.gov

Change

-qVars "COV1,COV3" \

to

-qVars "COV1,COV3,BRAIN_FC" \

Also check out this:

" -vVars variable_list: Identify voxel-wise covariates with this option.
Currently one voxel-wise covariate is allowed only. By default
mean centering is performed voxel-wise across all subjects.
Alternatively centering can be specified through a global value
under -vVarsCenters. If the voxel-wise covariates have already
been centered, set the centers at 0 with -vVarsCenters."

Gang