Dear SPM experts,
We performed a fMRI experiment in which subjects were tested twice 6
weeks apart. We have 4 fMRI runs at Time1 and 4 fMRI runs at Time2. The
fMRI centre were we work changed their headrest in between Time1 and
Time2, which resulted in 4-5 cm distances in Y and Z directions and
several degrees of pitch rotation between images at Time1 and images at
Time2.
We feel it is not reasonable to enter all 8 runs in the same realign
with such a big distance. Or is it?
We tried to move the Time2 time series using the "reorient image" option
in checkreg, so they would be in rough alignment with the time series at
Time1 before the realign, but found out that as long as the images are
not resliced, the realign ignores those changes. Is it ok to reslice the
images twice, once before and once after the realign? (we would like to
use dartel to register to the MNI space). Or is there a better solution
to our problem?
Thank you so much for your help
Patricia
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