Synaptic scaling rule preserves excitatory-inhibitory balance and salient neuronal network dynamics

Nat Neurosci. 2016 Dec;19(12):1690-1696. doi: 10.1038/nn.4415. Epub 2016 Oct 17.


The balance between excitation and inhibition (E-I balance) is maintained across brain regions though the network size, strength and number of synaptic connections, and connection architecture may vary substantially. We use a culture preparation to examine the homeostatic synaptic scaling rules that produce E-I balance and in vivo-like activity. We show that synaptic strength scales with the number of connections K as ∼ , close to the ideal theoretical value. Using optogenetic techniques, we delivered spatiotemporally patterned stimuli to neurons and confirmed key theoretical predictions: E-I balance is maintained, active decorrelation occurs and the spiking correlation increases with firing rate. Moreover, the trial-to-trial response variability decreased during stimulation, as observed in vivo. These results-obtained in generic cultures, predicted by theory and observed in the intact brain-suggest that the synaptic scaling rule and resultant dynamics are emergent properties of networks in general.

MeSH terms

  • Action Potentials / physiology
  • Animals
  • Brain / physiology
  • Excitatory Postsynaptic Potentials / physiology*
  • Inhibition, Psychological
  • Mice, Transgenic
  • Nerve Net / physiology*
  • Neuronal Plasticity / physiology*
  • Patch-Clamp Techniques / methods
  • Synapses / physiology*
  • Synaptic Transmission / physiology*