%0 Journal Article %A Kimberly L. Stachenfeld %A Matthew M. Botvinick %A Samuel J. Gershman %T The hippocampus as a predictive map %D 2017 %R 10.1101/097170 %J bioRxiv %P 097170 %X A cognitive map has long been the dominant metaphor for hippocampal function, embracing the idea that place cells encode a geometric representation of space. However, evidence for predictive coding, reward sensitivity, and policy dependence in place cells suggests that the representation is not purely spatial. We approach this puzzle from a reinforcement learning perspective: what kind of spatial representation is most useful for maximizing future reward? We show that the answer takes the form of a predictive representation. This representation captures many aspects of place cell responses that fall outside the traditional view of a cognitive map. Furthermore, we argue that entorhinal grid cells encode a low-dimensional basis set for the predictive representation, useful for suppressing noise in predictions and extracting multiscale structure for hierarchical planning. %U https://www.biorxiv.org/content/biorxiv/early/2017/07/25/097170.full.pdf