hi spm
we have a question about the output of the normalisation process for
fMRI. We have noticed that the origin of the normalised nr* files differs from
that of files at earlier stages (eg r* files). Despite the fact that
we carefully change the origin of the files to equate with that of
the EPI template image (using header edit) following normalisation
it reverts to a more superior location and our normalised images turn
out "squint".
We suspect that this has to do with the fact that during
normalisation, SPM reads origin information from the .mat files and
not the header (is this right?). We cannot delete the .mat files, because these
contain information about rotations which we have performed on the
images such that the slices are at the correct angle. Our question
is this: can you persuade SPM to read the origin location from the
header without deleting the .mat files?
the only solution we have come up with so far is to physically move
the images (using the up, left, etc tools in the display window) until
they align with the origin, rather than vice versa. Is this the only
way to do it, or is there something we have misunderstood?
thanks in advance for help
Chris Summerfield
departament psiquiatria i psicobiologia clinica
universitat de barcelona
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