Linking Memories across Time via Neuronal and Dendritic Overlaps in Model Neurons with Active Dendrites

Cell Rep. 2016 Nov 1;17(6):1491-1504. doi: 10.1016/j.celrep.2016.10.015.

Abstract

Memories are believed to be stored in distributed neuronal assemblies through activity-induced changes in synaptic and intrinsic properties. However, the specific mechanisms by which different memories become associated or linked remain a mystery. Here, we develop a simplified, biophysically inspired network model that incorporates multiple plasticity processes and explains linking of information at three different levels: (1) learning of a single associative memory, (2) rescuing of a weak memory when paired with a strong one, and (3) linking of multiple memories across time. By dissecting synaptic from intrinsic plasticity and neuron-wide from dendritically restricted protein capture, the model reveals a simple, unifying principle: linked memories share synaptic clusters within the dendrites of overlapping populations of neurons. The model generates numerous experimentally testable predictions regarding the cellular and sub-cellular properties of memory engrams as well as their spatiotemporal interactions.

Keywords: computational model; information binding; intrinsic excitability; memory allocation; non-linear dendrites; plasticity; simplified neurons; synaptic clustering; synaptic tagging and capture.

Publication types

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

MeSH terms

  • Action Potentials
  • Dendrites / physiology*
  • Memory / physiology*
  • Models, Neurological*
  • Nerve Net / physiology
  • Nerve Tissue Proteins / metabolism
  • Neuronal Plasticity / physiology
  • Subcellular Fractions / metabolism
  • Time Factors

Substances

  • Nerve Tissue Proteins