Ripples Make Waves: Binding Structured Activity and Plasticity in Hippocampal Networks

Neural Plast. 2011;2011:960389. doi: 10.1155/2011/960389. Epub 2011 Sep 27.

Abstract

Establishing novel episodic memories and stable spatial representations depends on an exquisitely choreographed, multistage process involving the online encoding and offline consolidation of sensory information, a process that is largely dependent on the hippocampus. Each step is influenced by distinct neural network states that influence the pattern of activation across cellular assemblies. In recent years, the occurrence of hippocampal sharp wave ripple (SWR) oscillations has emerged as a potentially vital network phenomenon mediating the steps between encoding and consolidation, both at a cellular and network level by promoting the rapid replay and reactivation of recent activity patterns. Such events facilitate memory formation by optimising the conditions for synaptic plasticity to occur between contingent neural elements. In this paper, we explore the ways in which SWRs and other network events can bridge the gap between spatiomnemonic processing at cellular/synaptic and network levels in the hippocampus.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Acetylcholine / physiology
  • Action Potentials / physiology
  • Animals
  • Brain Waves / physiology*
  • CA1 Region, Hippocampal / physiology*
  • CA3 Region, Hippocampal / physiology*
  • Carbachol / pharmacology
  • Cholinergic Agents / pharmacology
  • Humans
  • Locomotion
  • Memory, Episodic
  • Memory, Long-Term / drug effects
  • Memory, Long-Term / physiology*
  • Models, Neurological
  • Nerve Net / physiology
  • Neuronal Plasticity / physiology*
  • Rats
  • Sleep Stages / physiology
  • Sleep Wake Disorders / physiopathology
  • Sleep Wake Disorders / psychology
  • Spatial Behavior / physiology
  • Synapses / physiology
  • Wakefulness / physiology

Substances

  • Cholinergic Agents
  • Carbachol
  • Acetylcholine