Abstract
Interactions between the hippocampus and prefrontal cortex (PFC) are critical for learning and memory. Hippocampal activity during awake sharp-wave ripple (SWR) events is important for spatial learning, and hippocampal SWR activity often represents past or potential future experiences. Whether or how this reactivation engages the PFC, and how reactivation might interact with ongoing patterns of PFC activity, remains unclear. We recorded hippocampal CA1 and PFC activity in animals learning spatial tasks and found that many PFC cells showed spiking modulation during SWRs. Unlike in CA1, SWR-related activity in PFC comprised both excitation and inhibition of distinct populations. Within individual SWRs, excitation activated PFC cells with representations related to the concurrently reactivated hippocampal representation, while inhibition suppressed PFC cells with unrelated representations. Thus, awake SWRs mark times of strong coordination between hippocampus and PFC that reflects structured reactivation of representations related to ongoing experience.
•Prefrontal cortical neurons reactivate during awake hippocampal sharp-wave ripples•Distinct prefrontal ensembles exhibit excitation or inhibition during reactivation•Reactivation is coordinated across hippocampal and prefrontal populations•Coordinated hippocampal-prefrontal reactivation may support event memory retrieval
Jadhav, Rothschild et al. show coordinated reactivation of representations related to behavioral experience in the hippocampus and prefrontal cortex during awake sharp-wave ripple events. This coordinated reactivation is well suited to support awake memory processes.
