When pain signals arrive at the brain they are distributed to multiple regions, including the medulla, cerebellum, pons, limbic system and somatosensory cortex. At the same time the brain is also modulating incoming pain signals by sending down a countersignal from the cerebral cortex, diencephalon, midbrain, pons and medulla. Although the animation shows this to be occurring in order, this would best be understood as occurring simultaneously in a symphony of neuronal activity.