Hello Michaël,
I asked the same question some time ago and Jesper replied that this
(doing both realign & unwarp and including motion parameters in the
statistical model) might not always be a good idea
(www.jiscmail.ac.uk/cgi-bin/webadmin?A2=SPM;8b9a6bf5.04) I elaborated on
this some time ago
(www.jiscmail.ac.uk/cgi-bin/webadmin?A2=SPM;e0da3786.1009) and have
since then looked into the effects of motion and random regressors on
power, on the first and second level
(www.ncbi.nlm.nih.gov/pubmed/22036679). I hope that either of these
sources may be helpful to form your own opinion on this matter :)
Cheers,
Marko
Mouthon Michaël wrote:
> I conduct an event-related fMRI study.
> I have a conceptual question. If I use a Realign and unwarp procedure (by using the fieldmap toolbox) during my preprocessing, should I avoid including movement parameters as regressor in my fixed effect model? Do these regressors (in the model) correct too much the movement related activity if an unwarping was previously done or you can apply both corrections without an important loss of signal?
>
> Thank you in advance
>
--
____________________________________________________
PD Dr. med. Marko Wilke
Facharzt für Kinder- und Jugendmedizin
Leiter, Experimentelle Pädiatrische Neurobildgebung
Universitäts-Kinderklinik
Abt. III (Neuropädiatrie)
Marko Wilke, MD, PhD
Pediatrician
Head, Experimental Pediatric Neuroimaging
University Children's Hospital
Dept. III (Pediatric Neurology)
Hoppe-Seyler-Str. 1
D - 72076 Tübingen, Germany
Tel. +49 7071 29-83416
Fax +49 7071 29-5473
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http://www.medizin.uni-tuebingen.de/kinder/epn/
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