Fig. 5From: Recent Advances on Neuromorphic Systems Using Phase-Change MaterialsExperimental demonstration of LTP and LTD in a biological synapse showing synaptic conductance as a function of time. a The solid circle denotes the conductance arising from high-frequency tectonic stimulation which results in LTP, and the open circle indicates the conductance in the absence of tectonic stimulation. b The change in synaptic conductance stemming from low frequency stimulation, yielding LTD. The dotted horizontal line shows the conductance level without applying stimulation. Reprinted with permission from [5]Back to article page