Hi all,
Sorry if this is a re-post, but I’m not sure if the first one got through.

I’m really stuck on a problem I was hoping to get help with.

I’m having trouble determining the correspondence between ROIs in a surface-based annotation and those in a volume-based annotation generated using mri_aparc2aseg. I have some custom-generated surface annotations  and have been using a recently updated binary of mri_aparc2aseg which adds 10,000 to the values of left hemi annotation labels and 20.000 to the right hemi labels in the converted volume, to help distinguish the two hemisphere’s rois.

To check the correspondence between the surface and volume, I chose an roi 10386 from the volume. To check it
 on the surface I did the following in matlab:
 
 [v,l,ct]=read_anntotation('lh.fsavg_500_compact.aparc.annot');
 new=zeros(size(v));
 new(find(l==ct.table(386,5)))=1; % note the roi index should be 10,000 less that of the volume.
F=write_wfile('386.w',new,v);
 
 I did this for both the fsaverage surface and a single subject surface, and
 compared it with the volume representation for the same single subject. The
 attached pic called vol386 shows the roi in blue, overlaid on the volume
 parcellation in greyscale. It is located in the left inferior temporal lobe.
 
 The attached surf386 pic however, indicates this region is in the
 retrosplenial cortex for both the single subject (left) and fsaverage (right).
 Am I missing something here? Have I misunderstood the correspondence between surface and volume rois?
 
Thanks for your help,
 Alex

------------------------------------------

Alex Fornito
CJ Martin Post-Doctoral Fellow
Brain Mapping Unit
Department of Psychiatry 
University of Cambridge
Downing Site
Downing St, Cambridge 
UK CB2 3EB

Email: af397@cam.ac.uk
Phone: +44 (0) 1223 764670
Fax: +44 (0) 1223 336581

Australian Details:

Melbourne Neuropsychiatry Centre
National Neuroscience Facility
Levels 1 & 2, Alan Gilbert Building
161 Barry St 
Carlton South 3053
Victoria, Australia

Email: fornitoa@unimelb.edu.au
Phone: +61 3 8344 1861
Fax: +61 3 9348 0469