Dear Jeff,
the reason to not offer any modulation for longitudinal data is that the modulation would be the same for all time points. Because you are interested in finding differences between the time points the modulation would influence these measures only slightly and only by a systematic amount.
Best,
Christian
On Tue, 18 Aug 2015 18:58:05 -0400, Jeff Browndyke <[log in to unmask]> wrote:
>The VBM8 longitudinal pipeline creates wp1* and wp2* output files, which according to the manual denote that these files are unmodulated.
>
>Is there a particular reason why longitudinal tissue maps cannot be created in the pipeline to reflect non-linear only modulation (i.e., m0* appended) files?
>
>I took a peak in the cg_vbm8_longitudinal.m code and it looks like there are open flags for modulated data, but I don�t want to either 1.) misinterpret the wp* files or 2.) do something statistically/methodologically incorrect.
>
>Any ideas on how to tweak the pipeline to produce m0p1* and m0p2* tissue maps?
>
>Thanks,
>Jeff
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