[Freesurfer] Errors in Cortical Parcellation

Hey there,

I was excited to find out that Freesurfer has two atlases built in which do cortical parcellation as I am trying to do analysis on the precentral gyrus ROI only. However, when creating a mask showing the pre-central gyrus parcellation, I noticed that in the middle of the gyrus the algorithm fails and skips to the next gyrus over (the post-central gyrus). I added an image showing the failed parecellation (not sure if it shows up).

Is there any solution around this? Is there where I can change parcellation options to maybe help better restrict the automatic algorithm? Or is there an easy way to redirect/train the algorithm?

Thank you very much for any advice and your time,

Omer Tal, M.S.

UCSD Center for Functional MRI