[Freesurfer] PET voxelwise

Hi Freesurfer Community,

I am trying to run a vertex-wise analyses of PET data.

I have already performed bbregister. Next, I did mri_vol2surf for each subject, left and right hemispheres.

for i in `cat subjects`; do mri_vol2surf --src FS6_${i}_MPRAGE_Neuro.nii/pet/pet2free_fsl.mgz --out FS6_${i}_MPRAGE_Neuro.nii/surf/lh.PETSurface.mgh --hemi lh --regheader FS6_${i}_MPRAGE_Neuro.nii --projfrac 0.5 --interp nearest; done

Is this command correct? Visual inspection on freeview looks OK.

How may I derive the group average from these individual surfaces and perform the mri_glmfit?

Any help will be greatly appreciated.

Best Wishes, Eli