Reducing Physiological Effects in Resting State fMRI by Dephasing Blood and CSF Signals

Yongquan Ye¹, Ewart Mark Haacke¹

It is well known that the intravascular signals contribute about half of the functional contrast at 3T, and physiological effects also contribute to the BOLD signal. Although extensively studied in task/event related fMRI, the role of vascular and physiological effects in resting state (RS) functional connectivity is yet to be fully understood. By implementing flow dephasing with low VENC value, this study aims at estimating the contribution of the intravascular (IV) blood signal and physiological effects to local and long range resting state signal characteristics.