Hello,
I need your help and advice on the following topic. I wanted to realign fMRI
data with SPM. I first used "Slice Timing" to produce aV* files. This process
gave good results as far as I can judge. I then used "Realign" on those aV*
files, with sinc interpolation, the default (*) options and "yes" to sampling
correction.
If you visualize the resulting files (two of which I have attached to this
mail), you'll clearly notice that there is something wrong. Actually, on every
realigned volume that I have checked, the first and last slices are very
strongly artifacted. I went through the process twice, and I got the same,
disturbing, result twice, even though the curves included in the "spm99.ps" file
don't show anything abnormal.
Can this be related to the fact that we only have 8 slices per volume? We have
never had this problem before, when treating acquistions with 14-slice volumes.
Thank you!
Guillaume
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