Hi Anthony,

a couple of things. First, we do have a metric preservation term in the inflation, so that not too much metric distortion is incurred during the deformation. But the real answer to your question is that there is correspondene between the inflated and other (e.g. white) surfaces, so we can always transfer information like thickness, which is a propert of the white and pial surfaces, to be visualized on the inflated.

cheers, Bruce On Thu, 18 May 2006, anthony gallo wrote:

Hello all, Can some one edify me regarding how FreeSurfer is able to maintain the same basic brain geometry (hemisphere shape) when it creates an inflated file image. I would figure that some areas (because of deeper sulci) would blow up (produce more inflated surface) much differently than others thus not maintaining the basic shape. I was thinking that maybe the program just flattens it all period, but then I wouldn't really be able to explain how you can still view the respective cortical thickness data because that too must correspond with all the nooks and crannies.............

I appreciate your help, Anthony