Grasping the noise – applying brain vasculature as a priori for sLFO reduction in the BOLD-fMRI signal and the impact on subject identifiability

Motivation: Denoising systemic low-frequency oscillations (sLFOs) using global signal regression (GSR) can possibly impact the neural component of the BOLD fMRI signal. Goal(s): Our goal was to use the spatial relationship between the sLFO component of the BOLD signal and brain vasculature to perform a less aggressive form of GSR. Approach: We collected structural and functional images at 3T in ten subjects. We then used to temporal and spatial characteristics of the sLFOs to denoise the BOLD signal. Results: The spatial correlation between the sLFOs and venograms confirmed their underlying vascular origin. The performance of our novel denoising technique still needs to be evaluated. Impact: We propose a novel sLFO denoising method that uses the temporal and spatial patterns of physiological noise to preserve a larger fraction of the neural activity.