I don't think we have anything that will grow a mask on the surface. A slightly hacky way to do it would be to create a binary mask on the surface in which your seed vertex is 1 and all others 0 (you can do this on the cmd line with mri_volsynth with the following options --pdf delta --delta-crsf vertexno 0 0 0 0). You can then smooth it with mri_surf2surf. You can specify the number of dilations with the number of smoothing steps (--nsmooth-in), then use mri_binarize to threshold at some value just above 0 (eg, 10e-10).
doug Nathan Dankner wrote: > Hello all. I am considering using peak activation voxels (with > coordinates either in talairach or MNI space) gleaned from fmri > studies in our lab to determine a priori areas of interest for > examining group differences in cortical thickness. Is this something > that is possible in freesurfer? In particular, I would ideally like > to be able to tell freesurfer how large of an area to examine around a > particular peak voxel for each subject as opposed to tracing an ROI > each time. I am not particularly well versed in the technical aspects > of things such as blurring kernels, but I am assuming that the amount > of blurring done by freesurfer will affect the ideal circumference of > any sphere around this peak voxel. Any suggestions as to how to go > about this? Please let me know if any more information is necessary. > Thanks, > > Nathan > ------------------------------------------------------------------------ > > _______________________________________________ > Freesurfer mailing list > Freesurfer@nmr.mgh.harvard.edu > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer -- Douglas N. Greve, Ph.D. MGH-NMR Center gr...@nmr.mgh.harvard.edu Phone Number: 617-724-2358 Fax: 617-726-7422 In order to help us help you, please follow the steps in: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
