Scrubbing

Submitted by Miss Lima on Sun, 05/22/2016 - 13:42

Hello!

I´m doing pre-processing in DPARSF and as expected when i do scrubbing some of my subject loose some timepoints (the "bad" ones).  When i was doing analysis ins SPM i had some trouble in put the onsets once scrubbing had removed some timepoints ( i had much problem when scrubbing removed a lot of time points).  My question is, how should i proceed in this case? I mean, how to fill the onsets parameter ? Should i delete (cut) the bad timepoints or interpolate them when i´m doing scrubbing?
I know that DPARSF create some .txt files called FD_Power, FD_jenkison and FD_Vandjik.  Should i use all of them as regressors in SPM analysis? 

I hope you could help me!

Many thanks in advance.

Inalinda F. ( Miss Lima)

Forums:

YAN Chao-Gan

Mon, 05/23/2016 - 08:02

Hi,

Did you perform scrubbing regression on your functional data? If so, you can scrubb your onset series as putting the "bad time points" to 0.

For "FD_Power" etc., I think it's better for you to put the Friston 24 parameters as regressors in your model.

Best,

Chao-Gan

Miss Lima

Mon, 05/23/2016 - 16:00

Hello!!
Yes, I did perform scrubbing on my functional data. 
I´m sorry but I didn´t understand what you meant by " you can scrubb your onset series as putting the "bad time points" to 0 ". 
I do not use FRISTON 24 parameter regressor because i didnt perform nuisance regression (it was distorting my images, but that´s another problem problem that i will expose here later on).
Im my SPM analysis i was using as multiple regressor only the rp_a20160118_110546s801a1008.txt file in the realign parameter folder on DPARSF.But as i´m doing scrubbing should i use the FD_POWER txt file as regressor too? 

Thanks in advance

I

YAN Chao-Gan

Tue, 05/24/2016 - 01:00

Hi,

For a given condition, the regressor is something like (1s at corresponded onsets):
1 1 1 0 0 0 0 0 1 1 1 0 0 0 0

You can scrub on this series.

I don't suggest add FD_POWER as a regressor. Adding Friston 24 is better if you can figure out a way.

Best,

Chao-Gan