Figure 2.
Bandpass filtering and nuisance regression approaches used in 144 resting-state fMRI functional connectivity studies drawn from 200 randomly sampled studies. For approaches that applied spectral filtering (BpReg, RegBp, Filtering Only), mean values and standard deviations for the low-frequency and high-frequency cutoffs for the filter are reported, as is the relative frequency of bandpass, high-pass, and low-pass filtering. For the BpReg approach, studies that spectrally filtered a given nuisance regressor to match the filtered fMRI data and denoted Bp (Signal).