You can edit the label names in the accompanying metadata file of your Atlas - maybe a .txt or .lut file? You can edit that in a simple text editor.

From: freesurfer-bounces@nmr.mgh.harvard.edu <freesurfer-bounces@nmr.mgh.harvard.edu> on behalf of John Anderson <jb19790001@gmail.com>
Sent: Thursday, February 9, 2023 9:52 AM
To: freesurfer@nmr.mgh.harvard.edu <freesurfer@nmr.mgh.harvard.edu>
Subject: [Freesurfer] change labels name

External Email - Use Caution

Dear Freesurfer,

I have a volumetric atlas in nifti format. I can open this atlas in freeview. Using the Lookup Table>FreesurferColorLUT, I can see how every label has a specific color. When I move the mouse cursor over an area of this atlas. I can see the name of that region (label). My question is how can I edit the name of the regions in that atlas.

I am sorry if my question is basic. I couldn't figure out how to do it :(

Thanks for any advice you may provide.

John