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Hallo Marko,

Thank you so much. I found the relevant snippet to transform my rp file. I have in total three conditions (A, B and C) and each condition has been executed in a separate session. For. eg. Session1 with condition A, Session2 with Condition B and session 3 with Condition C. Its a block design with 20 seconds of active condition and 20 seconds of baseline. Each condition has its respective Baseline (B1, B2 and B3). I have included 24RP as one of the multiple regression in the first level in each condition hence the design matrix looks like

ConditionA +24RP+ ConitionB + 24RP + ConditionC + 24RP + C1+C2+ C3

If I want to see the contrast associated with motion, can i use F contrast with following input

1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

One followed by 24 zeros. Is it correct?? If not could you please help me with the correct input??


Thanks a lot in advance

Best,
Wu



On 29 June 2016 at 19:41, Marko Wilke <[log in to unmask]> wrote:
Wu,

the 24 parameters refer to the so-called Volterra expansion of the realignment parameters, which means you take the 6 and shift them in time and also square them. If you search the list archives, there are some snippets available to transfom your rp_... files to this effect. A good reference to start would be a 1996 paper from Friston et al. And yes, people have tried it with and without, and the literature suggests that there are benefits for doing this, as well as costs (as always in life :)

Cheers
Marko

 


--
____________________________________________________
Prof. 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
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 http://www.medizin.uni-tuebingen.de/kinder/epn/
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>>> Wu chen <[log in to unmask]> 29.06.16 13.34 Uhr >>>
Hello SPM experts,

I am a beginner in the field of SPM analysis. I am about to start the SPM analysis. I have some basic questions. I have heard that during first level analysis it is better to include 24 regressor as the motion paramters. At the end of realignment i have only six coluoms of such parameters and not 24.

Do i have to set any function somewhere in SPM to get 24 realignment parameters?

Is it absolutly mandatory to include it? What is White and grey matter nuissance regressor and how can i get it in SPM?

Has any one tried the SPM analyis with 24 and without 24 parameter as the regressor in the design matrix? Is there a referecen avaialble? 

I would really appreciate for your help.

Regards,

Wu