Resting-state functional connectivity modulates the BOLD activation induced by nucleus accumbens stimulation in the swine brain

Introduction: While the clinical efficacy of deep brain stimulation (DBS) the treatment of motor-related symptoms is well established, the mechanism of action of the resulting cognitive and behavioral effects has been elusive. Methods: By combining functional magnetic resonance imaging (fMRI) and DBS, we investigated the pattern of blood-oxygenation-level-dependent (BOLD) signal changes induced by stimulating the nucleus accumbens in a large animal model. Results: We found that diffused BOLD activation across multiple functional networks, including the prefrontal, limbic, and thalamic regions during the stimulation, resulted in a significant change in inter-regional functional connectivity. More importantly, the magnitude of the modulation was closely related to the strength of the inter-regional resting-state functional connectivity. Conclusions: Nucleus accumbens stimulation affects the functional activity in networks that underlie cognition and behavior. Our study provides an insight into the nature of the functional connectivity, which mediates activation effect via brain networks.