| I have a question about the relevance of the ac-pc orientation of
| EPI-volumes.
| We want to run a paradigm in which we want to cover the whole
| cerebellum. For that purpose we have to orient our slices not in in
| ac-pc level but much steeper.
|
| My question: How important is the ac-pc orientation for the process of
| normalization? If I set the origin at the anterior commisure isnt that
| enough to give a good normalized brain or do I have to reorient the
| epi-images? And if, is it enough to reorient them by using mat-files or
| do I have to use SPM 96 to reslice them?
I would recommend reorienting them by their .mat files using the <Display>
button. If you reslice the images, you will find that you get bits of the
images chopped off. Too the various spatial processing steps in SPM, the
edges of chopped off parts apear like edges of the brain or head. This can
introduce unwanted distortions during spatial normalisation.
All the best,
-John
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