Dear all,
I have been trying to use ArtRepair and I have some questions regarding the preprocessing I am doing, and I would be very grateful if you could answer some of them. The preprocessing I am doing is as follows:
1. “art_slice”: Normally the threshold has to be modified until it is inferior to 5%.
- IS IT OKAY IF THE THRESHOLDS ARE DIFFERENT FOR DIFFERENT PARTICIPANTS?
- WHAT TO DO IF THE MASK CREATED IS NOT ACCURATE (THERE SEEMS TO BE DATA OUTSIDE THE HEAD)?
2. Slice timing
3. Realign & reslice
(4). art_despike IF “visual inspection of the ArtGlobal figure uncovers greater than +/-1 % drift in the mean global signal across the entire time series”.
- IS THERE A WAY TO CALCULATE THE PERCENTAGE OF THE SIGNAL DRIFT IN ORDER TO CHECK IF IT’S GREATER THAN +/-1 %? (For example by calculating the % of decrease between the maximum and the minimum value OR the first and the last image?
5. Coregistration
6. Segmentation
7. Normalization
8. Smoothing
(9). art_global: apply if art_despike was not applied.
When using art_global, users are asked “always repairs 1st scan of each?”. IF I ALREADY DELETED THE TWO FIRST DUMMY SCANS, SHOULD I REPLY “YES” OR “NO”?
- IF THERE IS TOO MUCH MOTION, IS IT OKAY TO SKIP “art_motionregress” AND USE THE “.rp” FILE FROM THE REALIGMENT STEP AS MOTION REGRESSORS?
- WHEN USING MOTION REGRESSORS, IS IT BETTER TO LEAVE THE SCAN-TO-SCAN MOVEMENT THRESHOLD AT 0.5 mm/TR?
- IS IT A PROBLEM IF ART_DESPIKE IS PERFORMED FOR SOME PARTICIPANTS AND ART_GLOBAL FOR OTHERS?
Finally, I would like to know if you believe the preprocessing I described is correct or not.
I would be extremely grateful if any of you could answer to these questions, it would be very helpful!
Best,
Ariadna
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