Dorsoventral hippocampus neural assemblies reactivate during sleep following an aversive experience

The integration of spatial and emotional components into episodic memory relies on coordinated interactions between hippocampal circuits and emotion-processing regions. Although the dorsal hippocampus (dHPC) supports spatial memory consolidation through sharp-wave ripple (SWR)-associated reactivation, it lacks direct connectivity with key emotional centers such as the amygdala. In contrast, the ventral hippocampus (vHPC) is anatomically and functionally embedded within the emotional network. How the dHPC and vHPC coordinate during sleep to support the processing of complex contextual and emotional experiences remains unclear. Here we used simultaneous electrophysiological recordings from the dHPC and vHPC in rats during sleep following a spatial alternation task under aversive or rewarding emotional valence. We show that coordinated SWRs during non-rapid-eye-movement sleep orchestrate assembly reactivation across the dorsoventral hippocampus. Reactivation after the aversive task more closely mirrors the original neural patterns, driven by the increased recruitment of vHPC shock-responsive neurons and enhanced dHPC spatial replay during coordinated SWRs. Our findings identify a mechanism by which the hippocampus may integrate the spatial and emotional dimensions of an experience during sleep, potentially routing information to the broader emotional memory network.