A Novel Temporal Filtering Strategy for Functional MRI Using UNFOLD

Sebastian Domsch¹, Andreas Lemke¹, Sebastian Weingrtner¹, Lothar R. Schad¹

UNFOLD to increase sampling rates in fMRI to detect transient BOLD signal modulations requires temporal filtering before statistical mapping in the time domain is carried out. Low-pass filtering and zero-filling has been proposed. Both strategies are non-optimal since low-pass filtering degrades temporal resolution and zero-filling leads to serial correlations (non-white noise) known to bias linear modeling of neuronal responses. We propose a more sophisticated temporal filtering strategy intrinsically avoiding non-white noise to increase statistical inference.