The Ag diffusive dynamics of the chalcogenide-based diffusive memristor are utilized for the emulation of short- and long-term synaptic plasticity functions of biological synapses. The Ag/WTe₂/Pt memristor mimics the short-term/long-term potentiation (STP/LTP) and long-term depression (LTD) behaviors of the biological synapses with high accuracy. Further, the biological model of memorization is successfully demonstrated by the chalcogenide-based diffusive memristor device.