It's been a while since I've had a chance to look at the mailing list,
and now I'm now getting to some pretty old emails. Most are probably
too old to answer, but I thought that I should say something here...
"Modulation" is usually applied to the image segments, rather than to
the original T1-weighted images. By modulating the deformed images
(Jacobian change of variables -
http://en.wikipedia.org/wiki/Change_of_variable and
http://en.wikipedia.org/wiki/Jacobian ), you ensure that the sum of grey
matter (or whatever) is the same as it was in the original.
Best regards,
-John
-----Original Message-----
From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]]
On Behalf Of Kalani Matsumura
Sent: Wednesday, March 14, 2007 3:29 AM
To: [log in to unmask]
Subject: [SPM] modulation with spm5
Dear SPMers,
I have been using spm2 and am now making the switch to spm5. Previously
to do modulation of T1 images, I was using a function called spm_sn2def
to
create a matrix of Jacobian determinants, which were then multiplied to
the image (using spm_imcalc) to create the modulated image. However, I
can see that spm_sn2def is no longer used in spm5. Does anyone know
which
function to use for modulation with spm5? I think I should use
spm_get_image_def, but I want to check with more knowledgeable people if
there are any other functions to use. Thanks in advance, I appreciate
the
help provided by the experts on this mailing list.
Sincerely,
Kalani Matsumura
[log in to unmask]
Neurobehavioral Research, Inc.
Honolulu, HI
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