Here is a simulation of the 3-transistor excitable circuit using SPICE. In our article, we emphasis using 2-variable mathematical models of the form
The obvious question is whether SPICE makes the same prediction as our 2-variable (nodes Vm and Vb) model. Comparison of the plots in the article and the results below show that they agree. Note that the SPICE model uses 5 variables due to the additional 3 nodes associated with Q1 and Q2.
Vm is the positive-feedback excitatory variable, and Vb is the slow response inhibitory variable.
Here is oscilloscope screen showing actual data.
