I have a question with regard to the "Slice timing" when acquiring the data
interleaved: we acquire 20 slices, so if I want to take the middle slice as
reference slice, which number do I have to give SPM: 19 (which is my actual
middle slice the 10th in acquisition) or 10?
Another question regards the function "unwarp" within the realignment
procedure in SPM2: does it make any sense to do realign & unwarp when we
have not acquired a field map? If we enter the parameters of movement as
other regressors in the model afterwards, is this redundant with the unwarp
function or not? At the momoent, we make the realign & unwarp and
make "coregister" and "write mean image only" (i.e. we do not reslice the
other images) and enter the movement parameters in the statistical model
(as "other regressors").
Thanks for any help and suggestions,
Michèle
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