Hi, I've tried to extrapolate from the instructions for computing MNI coordinates (at each source location) from cortical surface (using cs_convert function), but the computation from volume based source grid seems a bit more convoluted. Within this structure I found only a GridLoc matrix, which doesn't appear to strictly correspond with vertices. There is also no head model.
I'm also curious if I'm right in assuming that per-subject head models computed from the group analysis source grid should have the same mni-coordinate per source. In other words, I can do direct statistical comparisons on the subject-wise data without projecting to default anatomy? Or am I mistaken here?