title: Hippocampal-Prefrontal Theta Oscillations Support Memory Integration.
abstract: Integration of separate memories forms the basis of inferential reasoning--an essential cognitive process that enables complex behavior. Considerable evidence suggests that both hippocampus and medial prefrontal cortex (mPFC) play a crucial role in memory integration. Although previous studies indicate that theta oscillations facilitate memory processes, the electrophysiological mechanisms underlying memory integration remain elusive. To bridge this gap, we recorded magnetoencephalography data while participants performed an inference task and employed novel source reconstruction techniques to estimate oscillatory signals from the hippocampus. We found that hippocampal theta power during encoding predicts subsequent memory integration. Moreover, we observed increased theta coherence between hippocampus and mPFC. Our results suggest that integrated memory representations arise through hippocampal theta oscillations, possibly reflecting dynamic switching between encoding and retrieval states, and facilitating communication with mPFC. These findings have important implications for our understanding of memory-based decision making and knowledge acquisition.
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, 6525 Nijmegen, the Netherlands. Electronic address: a.backus@donders.ru.nl.
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Backus
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, 6525 Nijmegen, the Netherlands; Max Planck Institute for Psycholinguistics, 6525 Nijmegen, the Netherlands.
authors.forename: Jan-Mathijs
authors.initials: JM
authors.lastname: Schoffelen
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, 6525 Nijmegen, the Netherlands; University of Konstanz, 78464 Konstanz, Germany.
authors.forename: Szabolcs
authors.initials: S
authors.lastname: Szebényi
authors.affiliation: University of Birmingham, Birmingham B15 2TT, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Hanslmayr
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, 6525 Nijmegen, the Netherlands. Electronic address: c.doeller@donders.ru.nl.
authors.forename: Christian F
authors.initials: CF
authors.lastname: Doeller
mesh_terms: D000293:Adolescent; D000328:Adult; D003657:Decision Making; D005260:Female; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D008568:Memory; D017397:Prefrontal Cortex / Q000502:physiology*; D013826:Theta Rhythm; D055815:Young Adult