Which 3dTshift method does fmriprep use?

Software Support
1

It seems that fmriprep uses the default method in 3dTshift to perform slice time correction based on the call to it from line 121 in stc.py copied below. According to the current docs for 3dTshift, that would be Fourier. Is this correct or does fmriprep somehow use a different method from 3dTshift?

slice_timing_correction = pe.Node(
        TShift(
            outputtype='NIFTI_GZ',
            tr=f'{metadata["RepetitionTime"]}s',
            slice_timing=metadata['SliceTiming'],
            slice_encoding_direction=metadata.get('SliceEncodingDirection', 'k'),
            tzero=tzero,
        )
2

Hi @Todd_Hare and welcome to neurostars!

While it still uses the Fourier interpolation method, it may use a different slice time ref (tzero) than default 3dTshift.

Best,
Steven

3

Thanks for the quick reply Steven!

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