Remote memories are thought to be formed in the hippocampus and gradually transferred to the anterior cingulate cortex. However, it remains unclear when and through what neural activity patterns the memory trace cells in the cortex acquire the ability to persistently store remote memories. This study will investigate cortico-subcortical circuit interactions during remote memory formation, consolidation, and retrieval, taking advantage of various imaging techniques. Furthermore, using pharmacogenetic and optogenetic methods, we will explore the mechanisms by which neural network activity contributes to forming and controlling the persistence of remote memory in memory traces.