That's an aliasing effect that arises because the original voxels were
added into their new locations (rather than sampled from their
original locations and scaled by the Jacobian determinants). It will
disappear after smoothing (for a VBM study), or by computing average
values within regions.
It's done this way so that the voxel counts are preserved exactly,
whereas sampling and scaling by the Jacobians does not preserve them
quite as accurately.
Best regards,
-John
On 16 January 2013 20:16, Aggie McMahon <[log in to unmask]> wrote:
> Hello again,
>
> After analyzing data with TOM8/DARTEL/VBM8 I noticed my images (m0wrp1*.nii) have some weird striation. Does anyone else have this issue? Furthermore, how much of an issue is it?
>
> Thanks!
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