“The postsynaptic membrane is the membrane that receives a signal (binds neurotransmitter) from the presynaptic cell and responds via depolarization or hyperpolarization” (Uniprot, n.d.). When the postsynaptic membrane permeability increases, sodium ions flow into the cell space, thus depolarizing it with a degenerating action potential (VanMeter & Hubert 2018 p.334). This makes neurons more easily stimulated and excitable.