hi,

i have been using mri_vol2surf to map individual functional data onto the fsaverage brain:

mri_vol2surf --src 003/bold/03.time.intval.resam+orig.BRIK --src_type afni --srcreg 003/bold/register.dat --hemi rh --projfrac-avg 0 1 10 --trgsubject fsaverage --out 003/surf/03.time.intval.fsave.mgh

each time i do this, i compare the mapping onto the curvature with the same functional mapped onto the individual brain:

mri_vol2surf --src 003/bold/03.time.intval.resam+orig.BRIK --src_type afni --srcreg 003/bold/register.dat --hemi rh --projfrac-avg 0 1 10 --out 003/surf/03.time.intval.orig.mgh --out_type mgh

and thus far it's always been a fantastic match. i was curious, how does the mri_vol2surf script match up the individual functionals onto the curvature of fsaverage? i had a theory that maybe it implicitly references the surf directory of the subject, so i made a new subject directory tree with the functionals of one subject (003) and the surf directory of another. vol2surf-ing the same functional in this new directory to fsaverage results in an identical mapping as to in the regular 003 directory. a similar SUMA function (mapicosahedron) maps functionals into an icosahedron space by first warping the individual anatomical. does freesurfer's mri_vol2surf work somehow without using this information?

thanks,
emily