Episodic Memory: Dynamic Modes for Constructing Episodes

The capacity to re-experience a moment from one's past, known as episodic memory, is critical for our ability to navigate the present and plan for the future. This article reviews and synthesizes over a half century of behavioral and neuroscientific research that has shaped our understanding of how we remember past events. This work has revealed complementary truths about episodic memory: Episodic memories seem to be based on traces of experience, carrying objective information about specific moments in time, and on imaginative reconstructions, built on a scaffold of prior knowledge. We propose that the tension between these perspectives can be reconciled by conceptualizing episodic memory not as a readout from a static memory system but as the outcome of two neurocognitive modes- a generative mode that facilitates schema-based inference and prediction, and a contextual mode that binds memories to context-specific anchor points. Drawing from experimental findings and computational models, we describe how multiple memory modes arise from dynamic cortico-hippocampal interactions, allowing episodic memory to be at once precise and constructive.