Previous research has shown that the formation of synaptic engrams in multiple brain regions at different stages after memory formation is necessary for the long-term stabilization of memory. In this study, we aim to develop a novel optogenetic technology and use it to analyze when and where in the brain synaptic engrams are formed during memory stabilization. Through the formation and manipulation of synaptic engrams, this research seeks to elucidate the neural circuits of memory and provide critical insights for understanding memory disorders.