Fig. 2
From: Uncertainty Propagation in Nerve Impulses Through the Action Potential Mechanism
In panel a two current pulses are applied to a deterministic neuron with the nominal values for the parameters listed in Table 2. The first pulse is not strong enough to elicit a spike, the second stronger pulse immediately triggers a spike. Panel c shows the probabilistic counterpart of this experiment assuming 20 % of variability in the nominal parameters 
and 
. Large error bars show that the first small current pulse can trigger action potentials in this instance. In panels b and d the stronger current pulse is applied first, immediately eliciting a spike. In the deterministic model shown in panel b, the second small pulse fails to trigger a spike when applied during the refractory period. In the probabilistic model d, large variability in the output indicates a second action potential, which would not be expected from deterministic predictions