Synaptic potentiation facilitates memory-like attractor dynamics in cultured in vitro hippocampal networks

PLoS One. 2013;8(3):e57144. doi: 10.1371/journal.pone.0057144. Epub 2013 Mar 20.

Abstract

Collective rhythmic dynamics from neurons is vital for cognitive functions such as memory formation but how neurons self-organize to produce such activity is not well understood. Attractor-based computational models have been successfully implemented as a theoretical framework for memory storage in networks of neurons. Additionally, activity-dependent modification of synaptic transmission is thought to be the physiological basis of learning and memory. The goal of this study is to demonstrate that using a pharmacological treatment that has been shown to increase synaptic strength within in vitro networks of hippocampal neurons follows the dynamical postulates theorized by attractor models. We use a grid of extracellular electrodes to study changes in network activity after this perturbation and show that there is a persistent increase in overall spiking and bursting activity after treatment. This increase in activity appears to recruit more "errant" spikes into bursts. Phase plots indicate a conserved activity pattern suggesting that a synaptic potentiation perturbation to the attractor leaves it unchanged. Lastly, we construct a computational model to demonstrate that these synaptic perturbations can account for the dynamical changes seen within the network.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials
  • Animals
  • Cells, Cultured
  • Hippocampus / cytology
  • Hippocampus / physiology*
  • Long-Term Potentiation / physiology
  • Memory / physiology*
  • Models, Neurological
  • Nerve Net / cytology
  • Nerve Net / physiology
  • Rats
  • Receptors, AMPA / physiology
  • Synaptic Transmission / physiology

Substances

  • Receptors, AMPA