Figure 1.

Example time series from the renewal (left) and nonrenewal (right) integrate and fire models. In both models, the threshold value between two consecutive firings is drawn uniformly within the interval [θ₀ − D, θ₀ + D]. The difference is in the reset rule whenever v reaches θ: for the renewal model, the reset value of the voltage immediately after an action potential is drawn uniformly within the interval [−D, D]. In contrast, the voltage v is decremented by a fixed amount θ₀ in the nonrenewal model.