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Dear Dr.Bruce Fischl
Thank you very much for your great sense of responsibility.
Sure, i have sent you a zip file named "Maedeh_results"(it was a rather big sized one so i had to send it through Wetranser). Hope you have received it.
However, a general question is that, according to freesurfer help the required arguments for "mris_ca_train" are :
mris_ca_train [options] <hemi> <canon surf> <annot file> <subject 1> <subject 2> ... <output file>

as it seems it gets one surf file(e.g sphere.reg),and one annotation file, but several subjects...so what does this surface file refer to?should i make an average of all subjects' .reg files? and also for the annotation file ! just one .annot is enough or i have to make an average of several annotation files?
if yes, how should i do that?
i would be grateful if you could help me.
Best regards
Maedeh,