A Comparison of Physiologic Modulators of FMRI Signals

Hanzhang Lu¹, Feng Xu¹, Uma S. Yezhuvath¹, Yamei Cheng¹, Rani Varghese¹

A critical prerequisite for fMRI to be possibly used for personalized disease diagnosis is that we have to understand and account for differences in fMRI signals across healthy subjects. Recently, much attention has been focused on the physiologic markers that can explain the inter-subject variations. Here we conducted visual-stimulation fMRI in a group of young, healthy controls and compared four potential modulators in explaining the variations in fMRI signals: baseline venous oxygenation, cerebrovascular reactivity, resting state BOLD signal fluctuation, and baseline CBF. It was found that these physiologic parameters in combination can explain up to 69% of the inter-subject variations.