Neural Organization of Episodic Memory and Navigation in Children and Adults

Episodic memory and spatial navigation are often viewed as interlinked, in part due to their shared reliance on medial-temporal lobe (MTL) structures. At the same time, there are important differences, for example, natural spatial navigation requires moving one's body through space while episodic memory does not. We investigated whether naturalistically encoded memories that were either episodic or additionally embedded in a navigational experience relied on overlapping or distinct neural networks. Children ages 8-13 years old and young adults viewed pictures of objects that they had previously encountered in real-world experiences, either on a tour of a new environment or seated in a room, along with novel objects. Univariate fMRI analyses revealed tour-related activity in entorhinal (ERC) and perirhinal (PRC) cortices that differed between early adolescents and adults. Functional connectivity between ERC and PRC for episodic memory decreased with age. Exploratory findings suggested behavior-driven connectivity among the hippocampus, ERC, and lateral occipital cortex to support reconstruction of the spatial context. Naturalistic episodic and spatial contexts are processed in the MTL, but these regions may interact somewhat differently in episodic and navigational contexts, and in late childhood and early adolescence versus early adulthood.