Hi Ben,
I would be pretty surprised if you can get a reasonable surface from the MNI152. I would have thought it was too blurry to distinguish many of the gyri from one another.
That said, if you do have one, you can make labels in the volume and sample them onto the surface with tksurfer by just loading them.
cheers, Bruce
On Tue, 8 Sep 2009 benjamin.deen@yale.edu wrote:
Hi,
I didn't generated the surface myself (a technician in my lab did), but I imagine it entailed the same process as for a subject, just using the MNI152 brain instead of a single individual's anatomical image. I'm hoping to find the location on this surface of several peak coordinates from past studies, so that I can present the results of an informal meta-analysis by drawing dots (or some such) at these locations on an image of the surface. Thanks,
Ben
Quoting Bruce Fischl fischl@nmr.mgh.harvard.edu:
Hi Ben,
I'm still confused. How do you get a surface from an MNI average? Or is it from the colin dataset? Can you tell us a bit more about what you are trying to do so we can see if we can help?
cheers, Bruce On Tue, 8 Sep 2009 benjamin.deen@yale.edu wrote:
Hi,
The surface isn't from an individual subject, but generated from MNI space itself. What exactly do you mean by sample it onto the surface? I could make an image file with value one at the coordinate of interest and zero elsewhere, and then overlay it on surface space and see where it lies, but it would be rather tedious to do this for each of the coordinates I'm interested in (about 30), so I'm wondering if there is a faster way. Granted, some of them may not lie on cortical surface.
Ben
Quoting Bruce Fischl fischl@nmr.mgh.harvard.edu:
Hi Ben,
any given MNI coordinate may or may not be on the surface of a subject. You can convert it to individual subject space then sample it onto the surface.
cheers, Bruce On Tue, 8 Sep 2009 benjamin.deen@yale.edu wrote:
Hi,
I'm wondering how to convert a single voxel coordinate in 2mm MNI152 space to a location on a cortical surface representation of MNI space generated by Freesurfer. My broader goal is to present a set of coordinates collected for a meta-analysis on surface space. Thanks,
Ben Deen Department of Psychology, Yale University _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer