I am running xcp-d on my output from fmriprep with --nuisance-regressors acompcor. After my run is finished, I found in the visual report’s Functional section: “As the aCompCor regressors were generated on high-pass filtered data, the associated cosine basis regressors were included. This has the effect of high-pass filtering the data as well.”
I am not sure if we should still use highpass filtering for Butterworth bandpass filter if the cosine-basis is already doing the high pass filter for me. in other word, should i set --lower-bpf to be 0 to disable high pass filter if i decide to use acompcor as my nuisance-regressor or should i still keep it. I currently have parameter:
Thank you for the swift reply Steven ! I am indeed thinking of making -lower-bpf to 0 but may i ask what is the equivalence of high pass threshold for acompcor’s cosine basis? By equivalence i mean does acompcor’s build-in high pass filtering has -lower-bpf at around 0.008 or is it around another number? Sorry if this question seems to be confusing, I am new to fmri analysis.
Hi Steven,
About –nuisance-regressors acompcor, I just would like to make sure of one thing. If I use the --nuisance-regressors acompcor in Xcp-d, the cosine_xx has been added to the confound matrix as the fmriprep suggested? Thanks.
Best,
Yufeng
