A bi-exponential conductance response function which is NOT reset when a second event arrives. In this resopect it differes from the SpikeResponseFunction which is reset.
When a spike arrives on the input port, an conductance change is triggered in the attached membrane with the given riseTime, fallTime, maximal conductance (conductance), reversal potential, Erev and total duration. For a smooth profile, the duration should be several times the decay time. If the decay time is set to be smaller than the rise time it will be ignored and an alpha function (x * exp(-x/tau)) will be used. This is the limiting form of a bi-exponential as the decay time approaches the rise time from above.
If the saturates flag is set, then the single synapses can saturate under repeated stimulation. For computational convenience, this is not implemented by imposing the maximal conductance, but rather by specifying a saturationFactor indicating what fraction of the post-synaptic receptors are involved in transmission of a single event. Another event occurring immediately would be scaled down by (1 - saturationFactor). The available receptors are assumed to recover at the same rate as the decay of the synaptic conductance (fallTime). Thus, a saturation factor of zero means that conductances sum indefinitely. A saturation factor of 1 means that two spikes in rapid succession have the same effect as a single spike.