Writing absolute values is something that may make a tiny bit of difference,
but only really to a few voxels in the background.
I figured that it may be a tiny bit more appropriate for fMRI, as fMRI images
are normally reconstructed from the modulus of a complex image, and contain
only positive values. Really however, I don't think it makes that much
difference.
Regards,
-John
| For fMRI data, SPM99b seems to defaults to using option "a" when reslicing.
|
| The spm_realign.m script indicates that option "a" writes absolute values
| in images which it indicates is more appropriate for fMRI.
|
| SPM96b doesn't seem to "write absolute values in images".
|
| Why is this appropriate for fMRI, and should it universally be used when
| reslicing fMRI data?
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|