摘要：Emotional contagion, a primary form of empathy, is present in rodents. Among emotional contagion behaviors, social transmission of fear is the most ***, we modified a paradigm used in previous studies to more robustly assess the social transmission of fear in rats that experienced foot-shock. We used resting-state functional magnetic resonance imaging to show that foot-shock experience enhances the regional connectivity of the anterior cingulate cortex(ACC). We found that lesioning the ACC specifically attenuated the vicarious freezing behavior of foot-shock-experienced observer rats. Furthermore, ablation of projections from the ACC to the mediodorsal thalamus(MDL) bilaterally delayed the vicarious freezing responses, and activation of these projections decreased the vicarious freezing ***, our results demonstrate that, in rats, the ACC modulates vicarious freezing behavior via a projection to the MDL and provide clues to understanding the mechanisms underlying empathic behavior in humans.