Conventional computers based on von Neumann architectures have limited performance due to the physical separation of memory and processor. To achieve sustainable development of advanced neuromorphic computing technologies in the post-Moore era, neuromorphic devices with an integrated memory-computer architecture have emerged as an alternative solution. Here, we demonstrate an optical modulation-based artificial synapse that achieves phototunable coordination of conductance by virtue of its excellent photoresponsive properties, and exhibits excellent optoelectronic synaptic behaviours, successfully simulating key behavioural features of biological synapses including stimulus reinforcement, training facilitation, and memory consolidation, and evaluating the predictability of device forgetting. This study has important implications for the implementation of hardware artificial neural networks and the simulation of perceptual systems.