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Hello afni experts,

I have a quick question regarding this topic.

I really liked the idea to also evaluate BOLD % signal change in my data as another quality check for motion.
I scaled the data using the code above and before calculating the stdev I would like to detrend it as recommended. For detrending I used the default setting in 3dTproject (so 3 polynomials). When looking at the detrended signal it looks ok for most voxels but in some I can still see a trend (highlighted in red in the images). Do you recommend to choose a higher polynomial or is there a good reason not too. Again I am processing the signal just to evaluate potential motion artifacts as QC. If I can choose a higher number for polynomials how do I know how high this number can be? Do I just keep running the analysis and checking the signal until I am satisfied with the detrended signal?



Thank you very much
Carolin



Edited 2 time(s). Last edit at 03/06/2023 04:12PM by carolin31.