Despite wide application of resting state functional connectivity (rsFC) in systems neuroscience, fundamental aspects of rsFC remain poorly understood. Concurrent multi-channel electrophysiological recording and fMRI were performed in rat striatum along with pharmacological manipulation of VTA dopamine neuronal activity. Results suggest that LFPs of different frequency bands contribute distinctively and differentially to the observed BOLD fluctuations, and that cross-frequency phase-amplitude coupling (PAC) is the organizing mechanism through which low frequency LFPs orchestrate neural activity that underlies the BOLD rsFC. Our data imply that where there is a synchronized low frequency LFP signal, there is also resting state BOLD functional connectivity. rsFC does not necessarily reflect structural connectivity.