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Dear SPM list

I'd be grateful for your help.  I've not found this on the list; I  
apologise if I've missed this, or if this is trivial.

Several papers describe that intra-session and inter-session  
variability may be improved by using a Volterra expansion of the  
movement parameters as covariates of no interest in the GLM.  For  
example -

Lemieux L, Salek-Haddadi A, Lund TE, Laufs H, Carmichael D, Modelling  
large motion events in fMRI studies of patients with epilepsy, Magn  
Reson Imaging. 2007 Jul;25(6):894-901.

Lund TE, Nørgaard MD, Rostrup E, Rowe JB, Paulson OB., Motion or  
activity: their role in intra- and inter-subject variation in fMRI.  
Neuroimage. 2005 Jul 1;26(3):960-4.


Can this expansion be done in the design specification (using the GUI  
for spm5) for covariates of no interest?

If no, can the spm_Volterra.m script be used with the rp_*.txt file  
to create the file of expanded movement parameters?

Many thanks for this;

Simon Glynn
Fellow, Epilepsy
University of Pennsylvania