Spike Responders
Synapses whose source neuron is a spiking neuron are called spike responders.
In general, when a spike arrives at a post-synaptic cell (the target neuron of the spiking neuron), a "wave" of activation is created. This is modeled using a "response function" which characterizes a synaptic current, the influx of chemicals into a target cell which occurs when vesicles are released from a source neuron.
Formally, while the weighted inputs to a target neuron are usually computed by taking the sum of the source activation times weights at time t, if the source neuron is a spiking cell that term is replaced by:
weight(t) x response function(t)
This is to say, what is passed on to the post-synaptic neuron is the value of the response function scaled by the strength of the weight. That being said, there are a number of unique response functions that dramatically change the utility of the spike interaction. The response function can be thought of as the wave form of the response to a spike.