Calculating event-triggered average synaptic conductances from the membrane potential

J Neurophysiol. 2007 Mar;97(3):2544-52. doi: 10.1152/jn.01000.2006. Epub 2006 Dec 6.


The optimal patterns of synaptic conductances for spike generation in central neurons is a subject of considerable interest. Ideally such conductance time courses should be extracted from membrane potential (V(m)) activity, but this is difficult because the nonlinear contribution of conductances to the V(m) renders their estimation from the membrane equation extremely sensitive. We outline here a solution to this problem based on a discretization of the time axis. This procedure can extract the time course of excitatory and inhibitory conductances solely from the analysis of V(m) activity. We test this method by calculating spike-triggered averages of synaptic conductances using numerical simulations of the integrate-and-fire model subject to colored conductance noise. The procedure was also tested successfully in biological cortical neurons using conductance noise injected with dynamic clamp. This method should allow the extraction of synaptic conductances from V(m) recordings in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Computer Simulation
  • Electric Conductivity
  • Electric Stimulation / methods
  • Guinea Pigs
  • In Vitro Techniques
  • Membrane Potentials / drug effects
  • Membrane Potentials / physiology*
  • Models, Neurological*
  • Neurons / physiology*
  • Occipital Lobe / cytology
  • Patch-Clamp Techniques / methods
  • Synapses / physiology*
  • Synapses / radiation effects