I'm not sure I understand what you are asking about. Do you mean in the aseg.mgz or the aparc+aseg.mgz? Unknown is usually just stuff outside of the head, but sometimes can be in the head (eg, with aparc+aseg.mgz).
On 02/22/2018 08:51 AM, Daniel van de Velden wrote:
Dear fellow colleagues,
in my study I use volumetric source spaces. In the process of creating them, I decided to identify all available volumelabels FreeSurfer "recognized" in the given mri image.
Every single subject inherits, despite all other volumelabels, a volumelabel called "Unknown". In an 3D representation of those "unknown" volumelabel coordinates I opine those points could also be part of other volumelabels like cerebral cortex or white matter.
Would you please give me a detailed explanation of the origin of this 'Unknown' label? Specifically in respect to the fsaverage "subject".
Best regards,
Daniel van de Velden
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