Hi, I know this has been addressed a bit before, but I remain confused! Apologies.

1…. The dentate anatomically has 3 layers [molecular layer/granular layer/polymorphic layer]. What layers exactly do Freesurfer output “GC_ML_DG” or “CG_ML" correspond to?

Granular layer only? Or Granular layer with polymorphic layer? Or Granular layer, polymorphic layer and molecular layer?

It’s mentioned in the Eugenio Iglesias’ article that the molecular layer of the dentate is included in the CA4 region. Is this where is it, or is it in the GC_ML_DG?

2…. By “molecular_layer_HP” does Freesurfer mean the ‘molecular layer’ i.e. ‘outermost’ band of

Subiculum, CA1, CA2/3? Or Subiculum, CA1, CA2/3 and molecular layer of dentate?

I would appreciate some clarification.. Wonderful application by the way. A great step forward for hippocampal research

Many thanks..

Dr Darren Roddy

Trinity College Institute of Neuroscience

Room 3.36, The Lloyd Institute

Trinity College Dublin

Dublin 2

+353 86 6087927