Hello all,

I'm working on creating a standard set of MNI ROI structures for our lab and have a few questions about the way that AFNI handles atlases:

1) I see that several atlases in AFNI are probabilistic. In FSL, these atlases are either thresholded at 0, 25, or 50. I was wondering if AFNI thresholds the atlases or if they are all thresholded at 0? I understand that given that atlases can be added, that this answer may differ by which atlas you're using. So is there a way to tell the threshold of the atlas (if there is one?). I've tried 3dinfo and cat on the HEAD files but don't seem to be able to find that information.

2) Before I work to segment the MNI_avg152T1+tlrc atlas myself, I was wondering if there is an existing repository of extracted structures in MNI space (e.g., Left Amygdala, Right Putamen, etc. etc.) that lives somewhere in the AFNI directory or somewhere else that is open source but I can't find?

Thank you so much!

Best,
Megan