Dear FreeSurfer Community...

1. For QDEC analysis, we have pre-computed smoothed data for the target fsaverage surface using the command: recon-all -s <subjid> -qcache.

then we obtained 'lh.thickness.fsaverage.asc ' using mris_convert. The procedure is here mris_convert -c ./lh.thickness.fsaverage.mgh \ $SUBJECTS_DIR/fsaverage/surf/lh.white \ lh.thickness.fsaverage.asc

Finally, we read the 'lh.thickness.fsaverage.asc ' in matlab using read_asc.m and met the following error. [S, v, f] = read_asc('/usr/local/freesurfer/subjects/lh.thickness.fsaverage.asc'); ??? Error using ==> fscanf Invalid size.

Error in ==> read_asc at 45 f = fscanf(fp, '%d', S(3)*5);

How to fix this problem?

2. In fact, I want to use BA Labels ( http://surfer.nmr.mgh.harvard.edu/fswiki/BrodmannAreaMaps) to extract the thickness of visual area.

And am I right in assuming that the contents of this file, are my thickness stats of my subject after being aligned to fsaverage space, and that each line is in the correct order that corresponds to each vertex in fsaverage/surf/lh.{pial,white} ?

3. What is the best approach to co-register a single subject to fsaverage space and for the results to have identical number of vertices and faces as fsaverage?

Any help would be appreciated. Thanks