Failures of normalisation usually arise when the initial positioning
of the images is not good (ie more than about 3cm or 15 degrees
mis-alignment). I'd suggest using Check Reg with your original scans
to see how their alignment compares with the images released with SPM.
If the alignment is poor, then the Display button can be used to
re-position the scans.
Best regards,
-John
On 24 June 2011 09:59, Laura Bled <[log in to unmask]> wrote:
>
>
> Dear list
>
>
> I am completely puzzled by the results of normalization in one subject. It
> just doesn't make sense (see attached image - CheckReg function and images
> obtained) The same slice is exposed - slice 90 for all steps - raw fMRI ,
> after slice timing , after realign, after normalization and after smoothing.
>
> Volumes are completely shifted in Y and Z projections after normlization.
>
>
> This happens in only one subject, nothing similar in any other subjects.
>
> I did try very different preprocessing steps - with inclusion and exclusion
> of mean image from the normalization, using movement parameters as multiple
> regressors, using artrepair toolbox and repair of bad volumes etc
>
> I would be grateful if I would get any help - I am completely helpless in
> this situation and can't afford excluding this subject from my analysis.
>
> THANK in advance
>
> Laura
>
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