A new stereology time-course study by Pfizer Inc. in collaboration with SRC Biosciences finds no neuroregeneration in the rat superior cervical ganglion (SCG) after neuron death. This study addresses the critical issue of neuroregeneration in the ganglia of the sympathetic division of the autonomic nervous system. Despite evaluating neuron numbers in the rat SCG at 1, 3, and 6 months after nerve death, postganglionic neurons were not restored. This work has important implications for recovery of the “flight or flight” response after surgery or traumatic brain injury. The SCG provides sympathetic innervation to many structures in the head, including the blood vessels in the cranial muscles and the brain, the choroid plexus, the eyes, the lacrimal glands, salivary glands and the thyroid gland.