Hi Christian,
Christian Gaser wrote:
> - modulation makes no sense for longitudinal data because you analyze relative differences
> between the scans of each subject and there is no need to correct for the volume changes due to
> warping, because the warping parameters are the same for all scans of one subject
I think modulation might still make sense for longitudinal data if
more than one subject is compared, especially if there are different
groups which may systematically differ in how much volume change is
needed to match the template.
I guess it depends on whether you want each subject's chronological
differences to get scaled up or down according to whether their brain
(or a particular structure in it) was smaller or larger than average.
If the groups differ at baseline -- and you want to pick this up in
addition to changes over time -- then I think modulation is probably
right. Open to argument though!
Best,
Ged.
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