Influence of dendritic morphology on axonal competition

Van Ooyen, A., and Willshaw, D. J. (1999). In: Artificial Neural Networks - ICANN 1999, 9th International Conference on Artificial Neural Networks, Edinburgh, UK, September 1999, pp. 1000-1005. [Full text: PDF]

Abstract

The development of nerve connections involves competition among axons for survival promoting factors, or neurotrophins, which are released by the axons' target cells. To study the inluence of the target's dendritic tree on axonal competition, we have extended our model of axonal competition to take into account the extracellular space around the dendrites. We show that spatial separation of innervating axons on the target's dendrites mitigates competition and permits the coexistence of axons. The model accounts for the finding that in many types of neurons a positive correlation exists between the size of the dendritic tree and the number of impinging innervating axons surviving into adulthood. Our results emphasize the importance of postsynaptic dendritic morphology in the development of specific patterns of nerve connections, on which the function of the nervous system depends.