Looking for suggestions and/or documentations about slice timing correction: I have multi echo (3) data, completing my preprocessing using Tedana’s T2* Optimal Combine method as part of my fMRIPrep pipeline. In the Tedana documentation, it states:
“If the TR is slow enough to necessitate slice-timing (i.e., TR >= 1 sec., as a rule of thumb), then slice-timing correction should be done before tedana .”
My TR=.9 - so I’m assuming I do not have to do slice-timing? Or is this 1 second just an estimation?
It is a difficult subject with no definitive answer. It seems to be depending on your experiment design, your preprocessing stream, your analysis and the algorithm used for slice-timing. You may want to read this nice paper:
This other paper showed that, in the worst case slice timing correction doesn’t change the results, but that in most cases, it improves the results - especially for event related designs:
But it is worth mentioning that pipelines such as the HCPPipelines do not use slice timing correction (HCP FMRI data uses TR of about 800 ms).