Do STDP synapses potentiate and depress at the same time? Consider the following scenario where two cells are connected by an STDP synapse: PRE and POST. PRE cell fires two action potentials 2 ms apart (A and C below).
Cell POST fires an action potential (B) equally between the two spikes of the PRE cell. Assuming the STDP curve is symmetrical, would this situation result in no net change of the synaptic weight?
It seems that since B occurs shortly after A, then that would potentiate the synapse. And B occurs shortly before C, then that would depress the synapse by an equal amount. Thus resulting in no net change.
Is it correct, that both depression and facilitation takes place in an STDP synapse simultaneously?