Best BIDS approach when you have two anatomical scans from a single testing session

I am searching extensively for an answer but I was unable to find one. Except for a vague statement in the BIDS wiki.

Let’s say we are scanning a participant and the flow of things goes like this:

  1. Localizer
  2. T1w-1
  3. Bold scan type 1 ~ 10 minutes
  4. Bold scan type 1
  5. Bold scan type 2
  6. **Something happens which requires the participant to removed from the scanner, such as going to the toilet, adjusting their ear in head coil or something like that. We prepare the participant again, put them inside the scanner. **
  7. Localizer
  8. T1w-2
  9. Bold scan type 3
  10. Bold scan type 4
  11. Field mapping

Here, bold scan type translates to a different kind of paradigm/experiment something that is testing something completely different than others (maybe a auditory vs. visual task, or resting state fMRI)

Assuming all of above happened during the same testing session (ie. the same day) what is the best approach to prepare the data for BIDS? Should we consider all bold scans which came after the second anatomical scan as a whole different session and put them as a second session in the participant folder? Or is there a better way?


I would say keep them in the same session, and you can add the acq-<acq> label to differentiate before and after leaving scanner, making sure to include descriptions of these labels in your dataset description.


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Thanks for your answer. And do you have any example on how to utilize acq label in this specific context? Or anyone else who is reading this, please share if you do.

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Thanks for this as well. I am looking for a more concrete example, such as a dataset that has something like this, so that it’s easier to apply. I will take what I see there as an example.