I computed the region areas by adding the areas of the triangular faces inside these regions using the spherical coordinates of the vertexs and the Heron formula for the triangle area.
Another thing: Should I use the sig.mgh file resulted from the mri_glm estimation as the input to the mri_surfcluster function in MonteCarlo simulations? (plus the .csd file of course). In advance thank you a lot Jorge --- Doug Greve <[EMAIL PROTECTED]> escribió: > How did you get the 15 mm^2 regions? And how did you > know that they are > 15mm^2? There are some complications with using the > raw vertex areas on > fsaverage. The total surface area of the average > will be wrong > (inevitable with the way that fsaverage is > computed). However, there is > a correction, and our tools take this into account. > > doug > > jorge luis wrote: > > >Hello all > > > >I have made deep changes in 9 regions of a left > >hemisfere of a subject surface after maped it onto > >the fsaverage subject sphere. The changes were made > to > >have areas close to 15 mm^2. I computed the areas > by > >add the areas of the faces inside the regions > >(computed using the vertexes spherical > coordinates). > >The freesurfer sphere mapping is based in minimal > >metric distortion, so, why I got the following > >differences?: > > > > > >Region Computed areas (mm^2) Computed areas > (mm^2) > > uing mri_surfcluster as explained before > > >with the fsaverage sphere > > 1 27.56 15.0522 > > 2 21.78 15.0946 > > 3 21.41 15.1087 > > 4 20.77 15.1501 > > 5 19.28 15.1797 > > 6 16.60 15.1918 > > 7 15.99 15.2781 > > 8 14.31 15.3373 > > 9 13.89 15.0541 > > > >In both cases the same surface vertexes were found > to > >be inside the regions > > > > > >Another thing: > > > >Should I use the sig.mgh file resulted from the > >mri_glm estimation as the input to the > mri_surfcluster > >function in MonteCarlo simulations? (plus the .csd > >file of course). > > > >In advance thank you a lot > >Jorge > > > > > > > >______________________________________________ > >LLama Gratis a cualquier PC del Mundo. > >Llamadas a fijos y móviles desde 1 céntimo por > minuto. > >http://es.voice.yahoo.com > >_______________________________________________ > >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 > [EMAIL PROTECTED] > 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 > > > ______________________________________________ LLama Gratis a cualquier PC del Mundo. Llamadas a fijos y móviles desde 1 céntimo por minuto. http://es.voice.yahoo.com _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
