Hi,
as yet there is not tool available for integrated slice timing and motion correction - it is still something the FMRIB is working on. Mostly, slice timing is performed first and motion correction thereafter. Implicitly, the major software packages streamline the preprocessing this way. However, depending on the effects of motion and slice timing differences you may be better off the other way around: Imagine a some cortical voxels next to subarachnoidal liquor. Here, motion may cause huge intensity shifts. When slice timing shifts are rather negligible, it is better (for these voxels) to correct for motion first. On the other hand, when you correct for motion first slice timing will be impeded to some extent. So for now there is no perfect solution. But watch this place...
Andreas
PS: I guess the best way is to keep motion low in your data and choose a TR / slice number where slice timing differences will not have a huge impact on your model, anyway (i.e. in relation to the HRF).
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Von: FSL - FMRIB's Software Library im Auftrag von Damian Stanley
Gesendet: Mi 16.02.2005 19:42
An: [log in to unmask]
Betreff: [FSL] slice time correction and motion correction
Hello,
On March 3rd 2003, Steve Smith posted this in a response to a list question
>BTW, I should point out that slice-timing-correction is not in general
>necessarily a helpful thing to do; the slight loss of temporal information
>(because of the necessary interpolation used to achieve the time shift)
>may outweigh the advantage of having perfect "slice timing". Furthermore,
>it is not very satisfying to have to do the timing correction as a
>separate stage from the motion correction; integrating these is something
>which we are working on for the future.
I was wondering what progress had been made on integrating timing and motion
correction. Is there a tool in the works or is it still on the "future"
list. If it is still on the future list, is there a general recomendation
for the order in which to do these two corrections? Thanks
-Damian
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