Jennifer,
Yes, this is definitely kosher. It is quite common to regress out csf,
white matter, and motion in a task-based model. Typically the
timecourses for csf and white matter are taken from 3mm-radius seeds
placed in areas of pure csf and white matter. I've included some text
from a recent paper describing how the seeds were chosen.
Jim
Regions of interest for regressors of no interest were obtained by
placing 3mm-radius seeds in both white matter (MNI coordinates
33,-62,24) and CSF (MNI coordinates
6,- 2,19), and using the six motion regressors that results from
spatial realignment in SPM5.
On 8/10/13, Jennifer Barredo <[log in to unmask]> wrote:
> Hi SPMers,
>
> I have some CSF/midline activation that looks like physiological
> noise/movement artifacts in my task contrasts. I've used CSF regressors in
> resting state models before to deal with this, but I've never seen anyone do
> this in a task-effects model. Is it kosher for me to include a CSF regressor
> in my task model? I've already added the movement regressors to my model.
>
> Thanks!
> Jennifer
>
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