DYNA : Dynamic Episodic Memory Networks for Augmenting Large Language Models with Temporal Knowledge Graphs in Continuous Learning
This work addresses the challenges of catastrophic forgetting and high retraining costs in continual learning with large language models (LLMs). The authors propose modeling episodic memory as a dynamic temporal knowledge graph—where events serve as nodes and timestamped directed edges represent relations—as an external, updatable memory for a frozen LLM. During inference, retrieval-augmented generation (RAG) is enhanced by combining random walks with centrality-based retrieval from this graph. This approach effectively incorporates new knowledge without requiring model fine-tuning and, for the first time, demonstrates that structural properties of the graph—such as the clustering coefficient—can predict retrieval performance. Experiments show that, across three temporal recall tasks, the method reduces forgetting by approximately 7% compared to fine-tuning baselines and improves temporal ordering accuracy by about 5% over standard RAG.