processing-scripts > Orientation Change in rest_res.nii?
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Feb 3, 2012 11:02 AM | Andreas Horn
Orientation Change in rest_res.nii?
Hello everybody,
thanks again for providing the preprocessing scripts, they helped me to understand a lot.
But now I have a question: Is there an output-file being generated which is the original resting-state scan with all residuals removed but still remains in the exact same voxel-space as the original scan?
Before, I thought that rest_res.nii will be in the exact same space whereas rest_res2standard.nii would be the same result warped into standard MNI space. But if I compare rest_res.nii with the original scan, they seem not to be coregistered to the same space anymore.
As I would like to perform my calculations in subject space and e.g. use grey-matter masks derived from the original space, it would be great for me to have a volume without nuisance signals in the original subject space.
Thank you so much once more, for any suggestions!
Andreas
thanks again for providing the preprocessing scripts, they helped me to understand a lot.
But now I have a question: Is there an output-file being generated which is the original resting-state scan with all residuals removed but still remains in the exact same voxel-space as the original scan?
Before, I thought that rest_res.nii will be in the exact same space whereas rest_res2standard.nii would be the same result warped into standard MNI space. But if I compare rest_res.nii with the original scan, they seem not to be coregistered to the same space anymore.
As I would like to perform my calculations in subject space and e.g. use grey-matter masks derived from the original space, it would be great for me to have a volume without nuisance signals in the original subject space.
Thank you so much once more, for any suggestions!
Andreas
Feb 7, 2012 08:02 AM | Maarten Mennes
RE: Orientation Change in rest_res.nii?
Hi Andreas,
the only difference between rest.nii.gz and rest_res.nii.gz orientation-wise, might be that rest.nii.gz is in RAI or ASL (or some other scanner-specific orientation), while rest_res.nii.gz has been oriented to RPI.
We apply the (re)orientation to RPI to both the anatomical and functional scan to make sure we are operating in the same (subject-) orientation. However, this should not be a problem for subject space calculations (in fact we try to use subject space calculations whenever possible). I would suggest to just reorient your grey-matter masks to RPI (or derive it from head.nii.gz which is the mprage.nii.gz reoriented to RPI).
Let me know if this is not working for you!
Maarten
the only difference between rest.nii.gz and rest_res.nii.gz orientation-wise, might be that rest.nii.gz is in RAI or ASL (or some other scanner-specific orientation), while rest_res.nii.gz has been oriented to RPI.
We apply the (re)orientation to RPI to both the anatomical and functional scan to make sure we are operating in the same (subject-) orientation. However, this should not be a problem for subject space calculations (in fact we try to use subject space calculations whenever possible). I would suggest to just reorient your grey-matter masks to RPI (or derive it from head.nii.gz which is the mprage.nii.gz reoriented to RPI).
Let me know if this is not working for you!
Maarten