Human memory formation is accompanied by rhinal-hippocampal coupling and decoupling

Nat Neurosci. 2001 Dec;4(12):1259-64. doi: 10.1038/nn759.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology
  • Adult
  • Biological Clocks / physiology*
  • Cortical Synchronization*
  • Entorhinal Cortex / anatomy & histology
  • Entorhinal Cortex / physiology*
  • Epilepsy, Temporal Lobe / physiopathology
  • Epilepsy, Temporal Lobe / psychology
  • Female
  • Hippocampus / anatomy & histology
  • Hippocampus / physiology*
  • Humans
  • Magnetic Resonance Angiography
  • Male
  • Memory / physiology*
  • Memory Disorders / etiology
  • Memory Disorders / physiopathology
  • Memory Disorders / psychology
  • Neural Pathways / anatomy & histology
  • Neural Pathways / physiology*
  • Neurons / physiology*
  • Neuropsychological Tests
  • Synaptic Transmission / physiology
  • Verbal Behavior / physiology