Hello,

I modified the annotation file rh.aparc.annot to ‘rh.myaparc.annot’ I can read it with read_annotation.m and it seems correct. (The modification is simply a subdivision of the middletemporal to 32 subregion named : middletemporal_1 …middletemporal_32).

I copied this ‘rh.myaparc.annot’ file to /usr/local/freesurfer/sibjects/fsaverage/label/rh.myaparc.annot (I did this because the original ‘rh.aparc.annot’ file was there.

When I run the mris_ca_label as done in the log file generated by recon-all command:

mris_ca_label chuv44 rh ../surf/rh.sphere.reg /usr/local/freesurfer/subjects/fsaverage/label/rh.myaparc.annot ../label/rh.myaparc.annot

I have an error:

GCSAread(/usr/local/freesurfer/subjects/fsaverage/label/rh.myaparc.annot): file magic #28002 != GCSA_MAGIC (ababcdcd)

mris_ca_label: could not read classifier from /usr/local/freesurfer/subjects/fsaverage/label/rh.myaparc.annot

How can I do to use this annotation file? Is it necessary to have GCS file for parcellation? If yes how can I create it with this annotation file. I don’t want to create my own atlas, I want to use the freesurfer atlas (35 entries) but just divide some of its regions.

If needed, I can send you my annotation file.

Thanks a lot