 |
 |
Hi Chris and everyone else!! indeed, we are looking at right ankle dorsiflexion and yes, I definitively agree that the activation seems to be quite posterior. the graph I posted has on x axis the number of scan (TR=3secs, 5 minutes of acquisition). on the y axis there are mm for blue, green and d line, and degrees for yellow, cyan and magenta line. I superimposed all the realignemnt parameters along with the block design to search for the eventual correlation. I attached in any case te SPM output of realignment. all my best marta 2010/8/26 Chris Watson <[log in to unmask]> > Is it right ankle dorsiflexion that you're looking at? > It looks pretty posterior to the motor strip; what does it look like > overlaid on a structural? > What's the scale (units) of the graph you posted? Can you post the output > of SPM's realignment? > > > Gandolla Marta wrote: > >> Hi everyone, >> I attached a pdf file instead of a docx of the previous e-mail. sorry >> for the inconvenience!! >> I'd need some help about realignment parameters effect that seems to be >> huge in the acquisition I will now describe. >> We have a 30 secs block design, starting from rest. The patient is >> performing active ankle dorsiflexion during on blocks. >> We did the following preprocessing steps: >> - realignment >> - coreg >> - normalize >> - smooth (6mm) >> then we implemented the GLM with a 8 columns design matrix (1-condition >> with the 30 secs block design, 2-7- realign param, 8- baseline) and we found >> zero activation (p<0.01 FWE corrected). >> we then chacked with the 2 columns design matrix (1-condition with the 30 >> secs block design, 2- baseline) and we found a quite important activation >> (fig.1). should we trust this activation? the realignemnt param plot along >> with the block design protocol is shown in fig.2. is it possible that all >> this effect depends on the correlation between the realignment parameters >> and the condition column in the design matrix? should trust only the design >> with the realignement parameters as covariats of no interest? we are >> thinking in this case why we don't see any activation... do we miss >> something? >> thanks for your help >> best regards >> marta >> >