Differential filtering of two presynaptic depression mechanisms

Neural Comput. 2001 Jan;13(1):69-85. doi: 10.1162/089976601300014637.


The filtering of input signals carried out at synapses is key to the information processing performed by networks of neurons. Two forms of presynaptic depression, vesicle depletion and G-protein inhibition of Ca2+ channels, can play important roles in the presynaptic processing of information. Using computational models, we demonstrate that these two forms of depression filter information in very different ways. G-protein inhibition acts as a high-pass filter, preferentially transmitting high-frequency input signals to the postsynaptic cell, while vesicle depletion acts as a low-pass filter. We examine how these forms of depression separately and together affect the steady-state postsynaptic responses to trains of stimuli over a range of frequencies. Finally, we demonstrate how differential filtering permits the multiplexing of information within a single impulse train.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Calcium Channels / metabolism*
  • Electric Conductivity
  • Electrophysiology
  • GTP-Binding Proteins / physiology*
  • Homeostasis / physiology
  • Models, Neurological*
  • Presynaptic Terminals / physiology*
  • Synapses / physiology
  • Synaptic Vesicles / physiology*


  • Calcium Channels
  • GTP-Binding Proteins