Figure 8.
Incorporating a refractory period in the one-step model. In this variant of the one-step model, a refractory period was incorporated after each fusion event, preventing subsequent release at the same docking site during 40 ms. Simulations are as in Fig. 1 (25 Hz). Starting from the same reference values as in Fig. 1, parameters p (A), δ (B), and r (C) are separately increased in the range 0–1. For certain parameter combinations (dark blue curves in A and B and yellow/green curves in C), a depression/facilitation sequence occurs. However, all features of the depolarization experiments are not reproduced (see text).