Hi Todd
> On a different topic, does anyone know where I can find example
> regressors that are placed in the GLM to model effects of non-interest
> such as biorhythms (cardiac/respiratory motion)?
There is at least one paper, and one of the points I have tried to make is
that these effects are indeed the main course of serial/temporal
correlations in fMRI. I have compared a model with regressors of no
interest (RETROICOR and expanded motion parameters) with the AR(1) model
in SPM2, which is also available in SPM5. In SPM5 it is, thanks to Will
Penny, possible to use higher order and local modeling of temporal
correlation for single subject analysis.
Best
Torben
[1] T. Lund, K. Madsen, K. Sidaros, W. Luo, and T. Nichols. Non-white
noise in fmri: does modelling have an impact? Neuroimage, 29(1):54–66,
Jan 2006.
>
> Thank you.
>
> Sincerely,
>
> Todd Penney
>
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