Integration of event experiences to build relational knowledge in the human brain

We investigated how the human brain integrates experiences of specific events to build general knowledge about typical event structure. We examined an episodic area important for temporal relations, anterior-lateral entorhinal cortex (alEC), and a semantic area important for action concepts, middle temporal gyrus (MTG). Participants underwent fMRI while watching sequences of novel events and recalling their temporal relations over two sessions one week apart. Across different contexts, the roles of these events could either be consistent, or conflict; integrative representations should weaken in the conflicting condition. We found integrative representations that emerged quickly in alEC, and only subsequently in MTG, which showed a significant change across sessions. Thus, alEC is important in building integrative representations early in learning and may be a gateway to semantic knowledge in MTG. We suggest that both episodic and semantic systems participate in integrating new information when it is aligned with their content specializations.