What Causes Short Term Synaptic Depression?

What Causes Short Term Synaptic Depression? What causes short term synaptic depression? synaptic vesicles What causes short-term depression at synapses? STD is caused by depletion of neurotransmitters consumed during the synaptic signaling process at the axon terminal of a pre-synaptic neuron, whereas STF is caused by influx of calcium into the axon terminal after spike