Characteristics
The stimulation of a silent synapse does not elicit EPSPs when the postsynaptic cell is clamped at -60 mV. Stimulation of a silent synapse will elicit EPSPs when the postsynaptic cell is depolarized beyond -40 mV. This is because they lack surface AMPAR to pass current at hyperpolarized potentials, but do possess NMDARs that will pass current at more positive potentials (because of relief of magnesium block) Moreover, the EPSPs elicited with depolarized membrane potentials can be completely blocked by APV, a selective NMDAR blocker.
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