Hello Freesurfer Experts!

Thank you in advance for considering this question.

I did a cortical thickness analysis (surface-based), and found a significant cluster. I found the average cortical thickness in this group, in the .y.ocn.dat file, which is great.

Now I want to find the average cortical thickness in the same cluster, in a separate group of subjects.

I tried using mri_segstats, but it doesn't seem to work:

mri_segstats --slabel $label --i $input --nonempty --excludeid 0 --avgwf test.dat --sum Test_SupParietal.sum

The error I am getting is:

ERROR: cannot do frame average without input volume

Any thoughts about a better way to approach this analysis?

Thanks again in advance!

-T