Hello,
I have some questions regarding the similarities and differences between
SIENAr and FSL-VBM.
Correct me if I'm wrong , SIENAr will measure group differences only in gray
matter areas which are located in brain edges or very close to brain edges
(since flow images are dilated) while from the other side FSL-VBM is able to
measure differences in all gray matter voxels defined by the gray matter
mask (produced in the first stages of VBM's analysis). So a direct
comparison of voxelwise changes -with both methods in a specific data set
for gray matter differences- will not present any overlapping areas (except
only from the brain edges). Is my assumption correct?
However in SIENAr there's a possibility to identify if a group difference is
caused by atrophy of the first group or growth of the second one or both
phenomena take place together. Is there any possibility in FSL-VBM to
disambiguate what's going on in areas identified with group differences?The
statistics produced after vbm analysis only depict (the areas and) the
significance of differences among the groups but not what actually goes on
there.
Thank you once more
Antonios-Konstantinos
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