I'm guessing that the anatomical scan was used for determining how to
map between your subject and the template data (ie it is what the
segmentation used). This is why the inverse normalised data is the
same resolution etc as your anatomical scan, rather than your
functional data.
To inverse normalise in a way to get the same resolution as your
original fMRI data, you may need to include an additional step in what
you do with the Deformations Utility. Try adding an "Identity
transform" to the list of things to compose, which should allow you to
define a bounding box etc based on one of your functional scans.
Best regards,
-John
On 3 November 2010 13:30, Merz, Susanne <[log in to unmask]> wrote:
> Dear SPMers
>
>
>
> I recently started using SPM , and am a bit confused about a problem I
> encountered. I hope some of you can help me spot where the problem comes
> from. I am currently trying to do an inverse normalization of the grey
> matter template, using the seg_inv_sn files produced by a segmentation job
> on my data. My problem is, that even though the reversed picture seems to be
> registered with the original (using check_reg to visually check that), the
> resolution is inconsistent with the original image. Using NaN for Voxelsize
> and BoundingBox, as the manual seems to instruct I get 64x64x30 voxels in
> the original image and 256x256x124 voxels in the reconstructed image. This
> is the case regardless if I use a grey matter template or the normalized
> subject data as a basis for reconstruction. The parameters I use are:
>
>
>
> preserve: 0
>
> bb: NaN NaN NaN
>
> NaN NaN NaN
>
>
>
> vox: [NaN NaN NaN]
>
> interp: 1
>
> wrap: [0 0 0]
>
> prefix: 'w'
>
>
>
> Any ideas what could be causing this would be greatly appreciated.
>
>
>
> Thank You
>
>
>
> Susa
>
>
>
>
>
>
>
>
>
>
>
> Susanne Merz, Dipl.Inf.
>
> PhD Student
>
> Aberdeen Biomedical Imaging Centre
> University of Aberdeen
>
> The University of Aberdeen is a charity registered in Scotland, No SC013683.
>
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