title: Human cortical-hippocampal dialogue in wake and slow-wave sleep.
abstract: Declarative memory consolidation is hypothesized to require a two-stage, reciprocal cortical-hippocampal dialogue. According to this model, higher frequency signals convey information from the cortex to hippocampus during wakefulness, but in the reverse direction during slow-wave sleep (SWS). Conversely, lower-frequency activity propagates from the information "receiver" to the "sender" to coordinate the timing of information transfer. Reversal of sender/receiver roles across wake and SWS implies that higher- and lower-frequency signaling should reverse direction between the cortex and hippocampus. However, direct evidence of such a reversal has been lacking in humans. Here, we use human resting-state fMRI and electrocorticography to demonstrate that δ-band activity and infraslow activity propagate in opposite directions between the hippocampus and cerebral cortex. Moreover, both δ activity and infraslow activity reverse propagation directions between the hippocampus and cerebral cortex across wake and SWS. These findings provide direct evidence for state-dependent reversals in human cortical-hippocampal communication.
authors: Department of Radiology, Washington University in St. Louis, St. Louis, MO 63110; mitraa@wusm.wustl.edu marc@npg.wustl.edu.
authors: Anish
authors: A
authors: Mitra
authors: Department of Radiology, Washington University in St. Louis, St. Louis, MO 63110.|Department of Neurology, Washington University in St. Louis, St. Louis, MO 63110.
authors: Abraham Z
authors: 0000-0002-3379-9627
authors: AZ
authors: Snyder
authors: Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63110.
authors: Carl D
authors: CD
authors: Hacker
authors: Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63110.
authors: Mrinal
authors: M
authors: Pahwa
authors: Institute for Medical Psychology, Christian Albrechts University Kiel, Kiel, Germany.|Department of Neurology and Brain Imaging Center, Goethe University Frankfurt, Frankfurt, Germany.
authors: Enzo
authors: E
authors: Tagliazucchi
authors: Department of Neurology and Brain Imaging Center, Goethe University Frankfurt, Frankfurt, Germany.|Department of Neurology, Christian Albrechts University Kiel, Kiel, Germany.
authors: Helmut
authors: H
authors: Laufs
authors: Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110.
authors: Eric C
authors: EC
authors: Leuthardt
authors: Department of Radiology, Washington University in St. Louis, St. Louis, MO 63110; mitraa@wusm.wustl.edu marc@npg.wustl.edu.|Department of Neurology, Washington University in St. Louis, St. Louis, MO 63110.
authors: Marcus E
authors: ME
authors: Raichle
mesh_terms: D058256:Brain Waves / Q000502:physiology*; D002540:Cerebral Cortex / Q000502:physiology*; D004569:Electroencephalography; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008568:Memory / Q000502:physiology; D000069077:Memory Consolidation / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D013702:Temporal Lobe / Q000502:physiology; D014851:Wakefulness / Q000502:physiology
keywords: cortex; dynamics; hippocampus; memory; sleep