title: Human memory formation is accompanied by rhinal-hippocampal coupling and decoupling.
abstract: In humans, distinct processes within the hippocampus and rhinal cortex support declarative memory formation. But do these medial temporal lobe (MTL) substructures directly cooperate in encoding new memories? Phase synchronization of gamma-band electroencephalogram (EEG) oscillations (around 40 Hz) is a general mechanism of transiently connecting neural assemblies. We recorded depth-EEG from within the MTL of epilepsy patients performing a memorization task. Successful as opposed to unsuccessful memory formation was accompanied by an initial elevation of rhinal-hippocampal gamma synchronization followed by a later desynchronization, suggesting that effective declarative memory formation is accompanied by a direct and temporarily limited cooperation between both MTL substructures.
authors.affiliation: Department of Epileptology, University of Bonn, Sigmund-Freud Str. 25, D-53105 Bonn, Germany. juergen.fell@meb.uni-bonn.de
authors.forename: J
authors.initials: J
authors.lastname: Fell
authors.forename: P
authors.initials: P
authors.lastname: Klaver
authors.forename: K
authors.initials: K
authors.lastname: Lehnertz
authors.forename: T
authors.initials: T
authors.lastname: Grunwald
authors.forename: C
authors.initials: C
authors.lastname: Schaller
authors.forename: C E
authors.initials: CE
authors.lastname: Elger
authors.forename: G
authors.initials: G
authors.lastname: Fernández
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000328:Adult; D001683:Biological Clocks / Q000502:physiology*; D003344:Cortical Synchronization; D018728:Entorhinal Cortex / Q000033:anatomy & histology / Q000502:physiology*; D004833:Epilepsy, Temporal Lobe / Q000503:physiopathology / Q000523:psychology; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008568:Memory / Q000502:physiology*; D008569:Memory Disorders / Q000209:etiology / Q000503:physiopathology / Q000523:psychology; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D009483:Neuropsychological Tests; D009435:Synaptic Transmission / Q000502:physiology; D014705:Verbal Behavior / Q000502:physiology