I have a group of subjects that I have run through the standard freesurfer (version 5.3) pipeline, for the same subjects I also have T2 volumetric data and I have created T1/T2 ratio images for each subject. I have registered the ratio images into Freesurfer space and used mri_vol2surf to create surface overlays at different depths into the cortex for each subject, and these look reasonable when displayed with freeview. I now want to create average subjects for the ratio images at each depth, but I'm not sure what's the best way of doing this? Any suggestions would be appreciated.

Thanks,

Richard