(i) Following injury, such as WNV infection, new neurons arise from reservoir cells, likely SLC18A2 glial cells, and receive contacts from intact axons in specific reflex pathways, usually within days. (ii) Input, whether synaptic or trophic, from these new synapses regulates the generation of a transcriptome consistent with the new neuron becoming part of the functional circuit served by the intact axon. ChAT, choline acetyltransferase. (iii) The new transcriptome sets the preferred projection direction of the new axon, with orally directed outgrowth being favored by ascending interneurons and excitatory motor neurons, intrinsic sensory neurons projecting circumferentially, and inhibitory motor neurons and descending interneurons extending anally. (iv) The glial scaffold facilitates branching of enteric axons as they diverge to their different targets (18), interneurons supply neurons in other ganglia over projection distances of more than 1 cm, and motor neurons enter the muscle, where they branch extensively. Synaptic connections are made between the original survivor and newborn neurons in the relevant pathway, selected by their expressed transcriptome. Activity in the pathway and retrograde feedback from downstream targets allow refinement of the transcriptome to its mature form.