Synaptic dynamics contribute to long-term single neuron response fluctuations

Front Neural Circuits. 2014 Jul 1:8:71. doi: 10.3389/fncir.2014.00071. eCollection 2014.


Firing rate variability at the single neuron level is characterized by long-memory processes and complex statistics over a wide range of time scales (from milliseconds up to several hours). Here, we focus on the contribution of non-stationary efficacy of the ensemble of synapses-activated in response to a given stimulus-on single neuron response variability. We present and validate a method tailored for controlled and specific long-term activation of a single cortical neuron in vitro via synaptic or antidromic stimulation, enabling a clear separation between two determinants of neuronal response variability: membrane excitability dynamics vs. synaptic dynamics. Applying this method we show that, within the range of physiological activation frequencies, the synaptic ensemble of a given neuron is a key contributor to the neuronal response variability, long-memory processes and complex statistics observed over extended time scales. Synaptic transmission dynamics impact on response variability in stimulation rates that are substantially lower compared to stimulation rates that drive excitability resources to fluctuate. Implications to network embedded neurons are discussed.

Keywords: cortical culture; cortical slice; electrical stimulation; microelectrode array; patch clamp; response fluctuations; single neuron; synaptic dynamics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / drug effects
  • Action Potentials / physiology
  • Animals
  • Animals, Newborn
  • Cells, Cultured
  • Cerebral Cortex / cytology
  • Dose-Response Relationship, Drug
  • Excitatory Amino Acid Antagonists / pharmacology
  • In Vitro Techniques
  • Long-Term Potentiation / drug effects
  • Long-Term Potentiation / physiology*
  • Nerve Net / drug effects
  • Nerve Net / physiology*
  • Neurons / drug effects
  • Neurons / physiology*
  • Neurotransmitter Agents / pharmacology
  • Nonlinear Dynamics*
  • Rats
  • Rats, Sprague-Dawley
  • Synapses / drug effects
  • Synapses / physiology*
  • Synaptic Transmission / physiology*


  • Excitatory Amino Acid Antagonists
  • Neurotransmitter Agents