Dear all,

We were previously using the original ABCD-rsfMRI sequence until a software update on our Siemens Skyra scanner required us to rebuild the sequence using the Siemens software/GUI. We successfully recreated the rsfMRI sequence (2.4x2.4x2.4, 60 slices, TE=39ms , TR=900ms, acceleration factor = 6).

However, we are now encountering an unusual issue during the denoising step in CONN. Specifically, the patterns for CSF and white matter signals appear distorted or atypical (please refer to the attached PDF). This issue was not present when using the original ABCD-rsfMRI sequence and affects all participants scanned with the rebuilt version.

We have attempted different preprocessing pipelines, including fMRIPrep with single-band reference and fieldmaps, but the issue persists.

Has anyone experienced a similar problem after modifying or recreating the ABCD-rsfMRI sequence? We would greatly appreciate any suggestions or insights you might have.

Thank you for your help! 

Best regards,
Elischa