Reward revaluation biases hippocampal replay content away from the preferred outcome

Abstract

Internally generated sequences of place cell activity can depict spatial trajectories to reward locations, suggesting a role in model-based behavioral control. A largely separate literature emphasizes reward revaluation as the litmus test for such control, yet the content of hippocampal sequences under revaluation conditions is unknown. We report that the content of sharp wave-ripple hippocampal sequences is biased away from the preferred outcome following reward revaluation, challenging the idea that such sequences reflect recent experience or trajectories toward a goal.\n\nAcknowledgmentsWe thank Nancy Gibson, Martin Ryan and Jean Flanagan for animal care and MinChing Kuo, Julia Espinosa and Eric Carmichael for technical assistance. We thank Elyot Grant for developing the SWR detection method used for the main analyses in this paper. This work was supported by the University of Waterloo and Dartmouth College (start-up funds to MvdM), and the Netherlands Organization for Scientific Research (NWO, grant 863.10.013 to MvdM).\n\nAuthor contributionsAAC performed experiments and pre-processed the data. AAC, YT and MvdM wrote analysis code. AAC and MvdM performed data analysis. MvdM wrote the paper with comments from AAC and YT.\n\nConflict of InterestThe authors declare no competing financial interests.