Summary of what happened:
I am running fMRIPrep v23.0.2 and trying to understand how fieldmap registration is handled. The documentation for this version mentions “minimal preprocessing,” which includes motion correction, field unwarping, normalization, bias field correction, and brain extraction.
In later versions, there is an explicit BOLD↔fieldmap registration step that outputs a transform file (e.g., _from-boldref_to-TOPUP_mode-image_xfm.txt). However, in v23.0.2, I do not see any equivalent registration outputs. I want to clarify whether the BOLD↔fieldmap registration is performed in v23.0.2 and how the field unwarping uses the fieldmap.
Version:
23.0.2
Environment (Docker, Singularity / Apptainer, custom installation):
Docker
Thank you for any clarification!