Hello Maria
>Hello,
>Thanks for your feedback. I still need clarification of my two concerns.
>1) I don't quite understand how to set my design matrix since there is no
> baseline condition to subtract the task from. What I do have is, one task
> (eyes closed)that continues throughout the entire 110 volumes acquired.
>
>
I think I understand what they did .. I said I think .. note so sure
They set a model were they entered as regressors the 6 motions
parameters, and extra parameters directly extracted from the data (whole
brain signal from a region ???, signal from ventricle and signal from
white matter). So now you have a model of regression with 10 regressors
(the 9 above + cste). Note that it sounds strange to me to perform a
global normalization during the preprocessing and to include the whole
brain signal from a region (but what it is?) and a cste reg that is the
mean over all voxels .. (whole brain sig = cste ?? or whole brain sig
already scale by the global normalization - maybe someone has an idea
?). Anyway, from that, I guess, they obtained a new time series where
all this stuff is regressed out.. i.e. they got the residuals and then
performed the correlation analysis on residuals between ROIs. Thus your
model should incorporate this kind of regressors .. but the goal is to
clean the data and thus you don't need 2 conditions.
> 2) I'm also not sure if this TRUELY translates to a PPI analysis in SPM or if
> it's something I won't be able to replicate using SPM.
>Comments on the VALIDITY of a resting state analysis are greatly appreciated.
>
>
pass
>Thanks for you time,
>Maria
>
No pblm, nice paper
Good luck
Cyril
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