I am guessing that you refer to the masking that is done. To avoid
some motion artifacts in the fMRI, only those voxels that correspond
to a point within the FOV of all of the original images are used. If
this is not the case, then that voxel is set to zero in all scans.
Best regards,
-John
On 20 December 2010 17:29, Jiang, Zhiguo <[log in to unmask]> wrote:
> Dear SPM community:
>
>
>
> Recently I ran into an annoying issue with Normalise:Write in SPM8. (Not
> sure about SPM5). Say,I have an estimate of the normalization(either from
> Normalise:Estimate or Segmentation of T1), then I apply the normalization to
> a series of images, ). Lets say, you have a subject whom you collected three
> runs of scans. In batch interface, you run Normalise:Write by selecting all
> functional images at once vs. using three modules each consisting one run.
> Leave all other parameters the same, you are expected to see same normalized
> images. The result is really annoying. You get slight different images. Not
> sure what causes the problem.
>
>
>
> To sum it up , Normalise:Write will generate different results depending on
> how you select the images (multisessions). If you select the multi sessions
> in one module , your results will be different from if you use multilple
> modules. Can someone point out what might be causing the problem? How I
> should select the images? I really have no idea of which results I should
> trust.
>
>
>
>
>
> Thanks a lot,
>
>
>
> Tony
>
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