Dynamic retrospective filtering of physiological noise in BOLD fMRI: DRIFTER

► New Bayesian method for removing physiological noise from fMRI data. ► Cardiac and respiration frequencies from reference signals with the IMM algorithm. ► Possible to estimate the frequencies from fMRI data if time-resolution allows. ► Separation of fMRI into activation and noise with Kalman filtering and RTS smoothing. ► Outperforms the RETROICOR method when physiological signals change much over time.