Dear Frederic,

I’ll defer to Jean Augustinack (CCed) for a more granular answer (pun intended), but here are my initial thoughts.

1. You can find the definition in Table 2 of the paper, which is open access: https://www.sciencedirect.com/science/article/pii/S1053811915003420 2. Yes. 3. Both. We initially subdivided but it was too hard to do it consistently, so we merged them.

Kind regards,

/Eugenio

PS: FSL is not FreeSurfer (FS) :-P

Juan Eugenio Iglesias Senior research fellow CMIC (UCL), MGH (HMS) and CSAIL (MIT) http://www.jeiglesias.com

From: freesurfer-bounces@nmr.mgh.harvard.edu on behalf of "briend, Frederic" briend@cyceron.fr Reply-To: Freesurfer support list freesurfer@nmr.mgh.harvard.edu Date: Tuesday, 8 October 2019 at 18:23 To: "freesurfer@nmr.mgh.harvard.edu" freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] [FSL] Hippocampus subregions question

External Email - Use Caution Dear FSL members, First, thanks for your great work about the hippocampus subfield. Second, I have some question about your subfield/subregions definitions:

1. Can you give me your actual definition of the GC-ML-DG in your last release (FSL6.0) of the hippocampus segmentation? Is-it possible to speak about granular cell layer, like used in the Ho, 2017 (Molecular psychiatry) article? 2. Moreover, is-it possible to say for the the hippocampal tail that it is comprised of portions of CA and dentate gyrus? 3. For molecular layer (ML), is it the ML of the CA subiculum sub volumes or the ML of the DG or both?

Thank you in advance,

--

Frederic Briend, PhD