I have a group of controls and patients that I have collected two
anatomical sessions for. Is there an argument for averaging the T1
scans prior to statistical analysis using VBM as opposed to using each
scan as an individual subject, thus all subjects essentially are
represented twice? Statistically speaking, would it make a large
difference in the result to lean in favor of one method over the
other?
One other question..Can anyone provide an argument for using the
Jacobian tissue probability modulation in DARTEL? My preliminary
result came out looking very odd and as I do not know much about this
Jacobian transform I wonder what more useful information (or increase
in SNR) can be drawn using this transform compared to standard tissue
probability maps.
Any information or links to information would be greatly appreciated.
Best,
--
Benjamin Pruce, R.A.
Psychological and Brain Sciences
Indiana University
Bloomington, IN 47401
|