| Description |
The hippocampus (HPP) plays an important role in episodic memory, or memory for an event that occurs in a specific place and time, and there is evidence to suggest that the HPP is involved in processing spatiotemporal information in order to form context;ual representations of memory events. The HPP is not a homogeneous structure, but instead is comprised of anatomically distinct subregions, including the dentate gyrus (DG), CA3, and CA1, associated with separate mnemonic processing functions that contribute to episodic memory formation. Specifically, the DG is thought to support spatial processing functions, whereas the CA1 subregion has been implicated in temporal processing. Despite considerable advances in our understanding of the unique contributions of HPP subregions to learning and memory processes, the role of the dorsal DG (dDG) in spatial processing as it relates to spatial representations is not entirely understood or agreed upon. Given the importance of spatial representations to spatial navigation and episodic memory function, the current investigation sought to further define the role of the dDG in spatial processing through a series of studies that explored the nature of spatial memory representations. The results suggest that the dDG plays a critical role in (1) the integration of multimodal information into unique representations of the spatial environment via conjunctive encoding, (2) the reduction of interference among similar spatial locations via spatial pattern separation, and (3) the formation of temporal associations among distinct spatial events via temporal integration. Taken together, the present findings provide evidence for a dynamic role for the dDG in spatial processing by demonstrating the importance of an intact dDG across a variety of spatial tasks and under a variety of learning and memory demands. |
