Hi Ben,
Partial answer to your question -
It's fine to use motion regressors with normalised and spatially smoothed images, it's common practice. Whether you'd get stronger results by doing smoothing and normalisation afterwards is an interesting question. Try both ways for one of your subjects and report back? My feeling is it won't make a huge difference.
Not sure about the Art_global package I'm afraid.
Best,
Peter.
> -----Original Message-----
> From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]]
> On Behalf Of Xu, Ben (NIH/NINDS) [E]
> Sent: 23 March 2014 15:41
> To: [log in to unmask]
> Subject: [SPM] Motion correction
>
> Hi,
>
> When using SPM8 with a set of efMRI data at the first-level analysis,
> can motion parameters be used as regressors in the design matrix with
> the normalized and smoothed EPI images? Is it same or better to use
> them with the unsmoothed and unnormalized images and normalize and
> smooth the beta or contrast images afterwards?
>
> Also, will it be sufficient to correct for motion using the Art_global
> software, say, with a "repair" threshold of 0.5mm (extent of motion),
> and not to include the motion parameters as regressors in the first
> level design matrix?
>
> Thanks for your help.
>
> Ben
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