Hi Kaiming,
I'm almost certain you are right at the medial line and what you are seeing is the transition from one hemi to the other.  Most likely the brain is slightly oblique and so the sagittal slice does not perfectly bisect the two hemispheres.
-Louis

On Mon, 10 Mar 2014, Kaiming Yin wrote:

Hi FreeSurfer guys,

Just want to ask a quick question. So I have been using freesurfer on the analyses on my brain-
however I have noticed in certain parts, there hasn't been any segmentations.

I have attached a picture, to show what I mean. Is there a reason for this? The blurry part kind
of sweeps across the whole brain. Is there anything then, that I can do in freesurfer to still
allow it to calculate the segmentation?

Many thanks,
Kaiming

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