Very interesting debate you keep here, gentlemen.
I went on and divided FI by the area in one reference and one pathological
subjects (and age matched references). Now it seems that the "NewFI" is quite
correlated with cortical thickness. It even decreases from the frontal,
through parietal to
[Bruce wrote]
sounds reasonable to me, but we should call it something else (normalized
FI/CI?)
Yes, dividing out area does look like a first step, justified by the way
the per-vertex values are calculated. This gives the result units of mm^-2,
which maybe has an interpretation something alon
sounds reasonable to me, but we should call it something else (normalized
FI/CI?)
On Mon, 19 Nov 2007, Rudolph Pienaar wrote:
Hi Graham -
First off, your observation that the FI seems correlated with area is
completely correct. I'm not sure if you have the FS source code? Anyway,
looking at t
On Monday 19 November 2007 09:07, Graham wrote:
> 1. DVE's description of the FI calc, which it looks like FS implements
> (assuming FS's k calcs are faithful -- that code is hard to follow.)
Yep - that the code can be hard to follow. Still, you can assume that FS's k
calcs are faithful. But on d
Hi Graham -
First off, your observation that the FI seems correlated with area is
completely correct. I'm not sure if you have the FS source code? Anyway,
looking at the relevant code in 'mrisurf.c', the
MRIScomputeCurvatureIndices(...)
function pretty much computes the folding index
Folks:
We're wondering about how FS's "folding index" corresponds to Van Essen's
calculation (J Neurosci, 1997 Sept 15).
In particular, do the FI values for each region factor out the area of the
region or not. When we plot them the FI values look extremely correlated
to area, but that does
