Encoding the timing of inhibitory inputs

J Neurophysiol. 2005 May;93(5):2887-97. doi: 10.1152/jn.00910.2004. Epub 2004 Dec 29.

Abstract

Many neuronal systems represent information by the timing of individual spikes, and it is generally assumed that spike timing predominantly encodes excitatory inputs. We show here that the timing of inhibition can also be explicitly encoded in spike times using time-dependent and voltage-dependent properties of a rapidly inactivating potassium channel (I(KIF)). In vitro recordings in rat dorsal cochlear nucleus show that the effects of inhibition on spike timing can long outlast the duration of the inhibitory potential and that this depends only on the membrane voltage change during the inhibitory postsynaptic potential. Modeling results show that small neuronal populations with a heterogeneous distribution of I(KIF) voltage dependence can robustly encode intervals of >100 ms between inhibition and excitation. Thus neuronal systems can detect and represent the precise timing of inhibition, suggesting the importance of inhibition in information encoding.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Action Potentials / physiology
  • Action Potentials / radiation effects
  • Animals
  • Animals, Newborn
  • Cochlear Nucleus / cytology*
  • Electric Stimulation
  • In Vitro Techniques
  • Models, Neurological
  • Neural Inhibition / physiology*
  • Neural Inhibition / radiation effects
  • Pyramidal Cells / physiology*
  • Pyramidal Cells / radiation effects
  • Rats
  • Rats, Sprague-Dawley
  • Reaction Time / physiology*
  • Reaction Time / radiation effects
  • Time Factors