Dear FreeSurfer,

We have been discussing the mean curvature provided by FreeSurfer software. As i understand the mean curvature is measured as 1/r and has a unit of 1/mm.

But

a) What is the curvature an expression of? Is it the degree of folding of the brain and is it the white matter surface or pial surface?

b) An increased value of mean curvature - does that mean an increase in folding of the brain?

c) What is the expected association between the mean curvature; and cortical thickness and surface area? Any suggestions of litterature?

I have read through two webpages below, but unfortunately the confusion still exist :-)

I am aware that this may be a simple question but the different measures of curvature (fx. gaussian vs mean curvature) made us discuss the differences and what it is an expression of. 

Best regards,

Kasper