Hi there,
I am fairly new to tractography and am trying to get my head around how to appropriately threshold my output. I have run tractography with a seed mask (a 5x5x5 voxel sphere) and two waypoints. I want to use a 25% threshold to only include voxels which are tracked in at least 25% of the samples.
My first question is, do I threshold for each subject by taking 25% of the waytotal? Or by taking 25% of the max intensity (fslstats -R option)? I have a feeling I should be using the waytotal, but I am not clear on this.
Secondly, not all subjects have the same waytotal. I have seen threads in this list about individual differences in "trackability" - is this what is being referred to? I've also read in a few threads that you should normalize by the waytotal, but I'm not quite clear on how to go about this.
Thanks in advance for your help!
Laura
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