Hello,
sorry to post very similar question again but we are stuck
with a few questions on DARTEL here - though intersubject coregistration
and statistical
robustness are much improved compared with standard SPM5 VBM.
(1) "DARTEL space" vs. "absolute" MNI space:
We noted that the 6th (=last) template is systematically shifted in some
areas we
are very interested in (e. g . the hippocampus comes to lie 3-4 mm more
superior than the original templates and the colin MNI single brain) - it
brings a bit of a problem when using MSU or other MNI based localisation
tools.
Is there some trick to remain in MNI space and at the same preserve the good
intersubject registration?
(2) Can 1x1x1 mm3 images be written out form 1.5 x 1.5 x 1.5 mm3 flow fields,
or does the process need to be started at the higher resolution from scratch?
(3) Smoothing: We stepped down from 12 mm to 8 mm with DARTEL, which wrt
some result aspects seems "ok", however, is there an objective way to get
out of
the arbitrariness in choosing the kernel size?
Thanks very much for your help,
best regards,
Philipp
Max Planck Institute of Psychiatry
NMR Research Group
Kraepelinstr. 2-10
80804 Munich
Mail: [log in to unmask]
Phone: 0049-89-30622-413
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