Axonal geometry as a tool for modulating firing patterns

Neurons generate diverse patterns of activity for various functions. Revealing factors which determine neuronal firing patterns is fundamental to a better understanding of brain activity and coding. Traditionally, the space clamp model has been used to investigate neuronal electrical activity. In this paper, we study the Hodgkin-Huxley cable model, taking into consideration axonal geometry. We examine the influence of morphology on neuronal activity, exploring neuronal response to constant current stimuli injected into one end of fiber-like axons of different lengths and radii. We demonstrate novel patterns of firing, including a finite number of spikes and series followed by failures, and under some specific current stimulus regimes, we also detect irregular behaviors. Our results illustrate various means in which the pattern of activity may be regulated by axonal structure, suggesting this mechanism is instrumental in information coding of physiological, as well as deforming pathological conditions.