Dear SPMers,
I'm currently trying to do some first steps with AlphaSim by B.D. Ward.
For the simulation, the spatial correlation of voxel intensities is
crucial.
If I understand it correctly, images are smoothed at two points during
preprocessing: first during Realignment (default of 5mm FWHM) and then
during Smoothing (8mm default). Do both steps generate spatial correlation
of voxel intensities?
Secondly, what impact does it have that the standard SPM template I'm
using for normalisation is already smoothed with 8mm?
With these two things in mind: does it make sense at all to use an FWHM of
less then 5 or 8 mm, respectively, for smoothing?
Thank you for your help.
Best wishes,
Tim
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