Chapter 5 Modeling and Competition in the Nervous System: Clues from the Sensory Innervation of Skin

Publisher A fundamental feature of the modeling of neuronal connections is the phenomenon of competition, the inevitable outcome of too many nerves chasing too few targets or target sites. Competition could be based upon other determinants, including the possibility that target tissues themselves may regulate the number or availability of target sites. This chapter is directed toward discovering the mechanisms involved in modeling and in competition, utilizing as target tissue the skin of salamanders, rabbits, and rats; the nerves studied contribute to the low- and high-threshold mechanosensory innervations of skin. Some of the results help in the understanding of how nerve territories develop; the best characterized of these in the peripheral nervous system of vertebrates are the sensory dermatomes. Based on the studies of the sensory innervation of skin, a number of the likely processes and conditions are itemized that could influence the outcome of potential competition among nerves for target tissues or specific target sites.