rsfMRI and Physiology

From https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8090775/

….To come full circle, in resting‐state functional MRI (rs‐fMRI) analysis, the CSF signals (mainly from the ventricles) are routinely taken as a surrogate of cardiac pulsation, and used in nuisance regression when computing functional connectivity, which is primarily based on signals found below 0.1 Hz (Caballero‐Gaudes & Reynolds, 2017; Chen et al., 2012; Chen, Lu, & Yan, 2018; Chuang et al., 2019; Jo, Saad, Kyle Simmons, Milbury, & Cox, 2010; Johnen et al., 2015; Parkes, Fulcher, Yücel, & Fornito, 2018; Yan, Craddock, Zuo, Zang, & Milham, 2013).