Dear FreeSurfers,

I am doing some thing similar to the post from Zhiwei (https://www.mail-archive.com/freesurfer@nmr.mgh.harvard.edu/msg40540.html). I want to map visual topographic probabilistic maps (http://scholar.princeton.edu/napl/resources) from Princeton university onto the fsaverage. After converting these maps from SUAM 1d.dset format to FreeSurfer .gii format, I tried to map them onto fsaverage6 as annotation files in tksurfer. The following is the error message I got in tksurfer:

mrisReadGIFTIfile: malformed data array [0] in file /Volume/DATA/Studies/FS/SubjectData/fsaverage6/maxprob_surf_lh.gii: num_vertices=198812 num_cols=1 expected nvertices=40962, num_cols=1

The probabilistic map (maxprob_surf_lh.gii) is composed of two columns, the first one being node index ranging from 1 to 198812 and the second one being node value (nodes/vertices that belong to a certain surface ROI get a certain value, the rest of the nodes get the value of zero in the second column). These maps have been created in icosahedron surface space (using SUMA's MapIcosahedron -ld 141) using Buckner40 dataset. Taking into account that fsaverage is also derived from this dataset I don't understand why there is no vertex correspondence between these two surface files. One should note that these files are 1d vectors, and therefore, no auxiliary information such as label and parent surface, etc is preserved in these files.

With this intro, my question is how project these maps onto the fsaverage so they can be easily visualised in FreeSurfer?

Best,

Fatemeh Molaeii

Max Planck Institute for Biological Cybernetics Spemannstr. 41 72076 Tübingen Germany