Dear Kelly,
there are a couple of possible explanations and things you can try:
1. Did you perform slice timing correction? If not, try it. If yes,
check your TR (seconds) and slice times (order or milliseconds).
2. If those stripes are already visible in your raw data or the
(normalized) mean image, they might have been caused by subject movement
at the very beginning of your recording in the case you used some kind
of parallel imaging technique. When present also in the mean image, it
will be difficult to really get rid of this artifact.
3. If everything else fails, you can apply more than the usual smoothing
to your data. I guess with "interleaved design" you mean interleaved
slice acquisition, which could be helpful here since it might reduce the
residual error after smoothing.
Good luck,
Manfred
Am 02.02.2018 um 18:31 schrieb Kelly Vaughn:
> Hello SPM experts,
>
> I am hoping someone can help me understand and fix an artifact that I see in my betas of interest at the first level. It looks like bright stripes/bands visible in the sagittal plane. This artifact appears in the majority of my subjects and seems to align with the slice orientation. I used an interleaved design.
>
> So far, I have done motion correction and despiked the data using ArtRepair. This did not solve my problem. Does anyone have any suggestions of what else to try?
>
> I am attaching the sagittal view of one of my betas so that you can see the striping/banding, and an image that shows the results of motion correction and despiking that I did.
>
> Thanks in advance,
> Kelly Vaughn
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