I agree. You could look at the jacobians across subjects, which will sort of get at what you want, or surface area by parcellation unit is a good idea. On Fri, 23 Feb 2007, Don Hagler wrote:
Just a comment: Surface area on a vertex-wise basis doesn't seem very informative. Before topology fixing, the surface area should be about the same for all vertices (differences should be more or less random). Topology fixing will add or remove vertices, so the surface area in a "fixed" region will go up or down depending on the type of defect. So if you do a vertex-wise group average of surface area, you will possibly get a map of where you are most likely to get topological defects. On the other hand, doing a group-level analysis of total surface areas within cortical parcellations is more likely to be meaningful.
From: "Goldman, Aaron (NIH/NIMH) [C]" aarong@mail.nih.gov To: freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] surface area Date: Thu, 22 Feb 2007 14:46:16 -0500
Hi, I was interested in comparing surface area between two groups on a node-by-node basis (something like average area of the triangles touching each node) and noticed there were automatically-generated files named lh.area and lh.area.pial
I was wondering if these files contained the appropriate data for doing something like that, and if so whether there's any documentation you can recommend on how they are generated in Freesurfer.
Thanks,
-Aaron-
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
The average US Credit Score is 675. The cost to see yours: $0 by Experian. http://www.freecreditreport.com/pm/default.aspx?sc=660600&bcd=EMAILFOOTE...
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer