A 2-state open/closed model quantitatively reproduces the 6-state model.

<p><b>A</b>: histograms of interspike interval (ISI) distribution for both the 6-state and the simplified models. The ISI is defined to be the waiting time between successive spikes. Each histogram contain an equal number of samples (180). <b>B</b>: comparison of average ISI, average peak value of ( in the model) and average spike duration. All distributions were computed at a constant .