In our model some assumptions are taken to simplify calculations. Very primitive but fast numeric integration method is used, so the results are not so exact when dealing with big forces. Framsticks neurons use a simple weighted sum of input signals. Excitation influences neuron state, which has some inertia.
Stronger signals can change the state faster than weak signals.
The state goes up when the input is positive and falls down when theinput reaches zero. Note that in this example the neuron's state can fall below zero due to its inertia. Short but strong impulse gives similar results to a weak and long one. Later signal changes do not influence the output. Neuron properties can be changed by some special genotype elements inside neuron descriptions.