How brain reacts to attack at a local region

The brain function is a network phenomenon. The architecture of brain networks has been extensively studied in multiple species. However, exactly how the brain network reconfigures when a local brain region stops functioning is virtually unknown. By combining chemogenetic and resting-state functional magnetic resonance imaging (rsfMRI) methods in an awake rodent model, we investigated the causal impact of inactivating a hub region (i.e. dorsal anterior cingulate cortex) on brain network properties. We found that disrupting hub activity profoundly changed the function and organization of the default-mode network (DMN), as well as DMN-related behavior (i.e. quiet restfulness). It also altered the topological architecture of the whole-brain network in network resilience, segregation and small worldness, but not network integration. These data provide direct evidence supporting the hypothesis that acute dysfunction of a brain hub can cause large-scale network changes. They also comprehensively document the differential impact of inactivating a hub versus a non-hub on network dynamics.