Stochastic Ion Channel Gating and Probabilistic Computation in Dendritic Neurons
The electrical signals underlying neural computations are mediated by membrane ion channels. Although these ion channels are well known to operate stochastically, most computational models of dendritic neurons instead make the approximation that ionic conductances are deterministic. We review the basic mathematical considerations underlying this approximation and new efficient simulation tools that allow it to be evaluated systematically. We show how this approximation breaks down for dendritic neurons, with the relative functional influence of stochastic ion channel gating likely to depend strongly on neuron type. An important consequence of stochastic gating of ion channels may be that it causes dendritic neurons to integrate synaptic inputs probabilistically, rather than in the all or nothing fashion predicted by deterministic models.
KeywordsPermeability Hines Diba
- Cannon RC, O’Donnell C, Nolan MF (2010) Stochastic ion channel gating in dendritic neurons: morphology dependence and probabilistic synaptic activation of dendritic spikes. PLoS Comput Biol 6(8)Google Scholar
- Gillespie DT (1977) Exact stochastic simulation of coupled chemical-reactions. Abstr Paper Am Chem Soc 173:128Google Scholar
- Hille B (2001) Ion channels of excitable membranes, 3rd edn. Sinauer, Sunderland, MAGoogle Scholar
- Koch C (1999) Biophysics of computation: information processing in single neurons. Computational neuroscience. Oxford University Press, New YorkGoogle Scholar
- Nolan MF, Malleret G, Dudman JT, Buhl DL, Santoro B, Gibbs E, Vronskaya S, Buzsaki G, Siegelbaum SA, Kandel ER, Morozov A (2004) A behavioral role for dendritic integration: HCN1 channels constrain spatial memory and plasticity at inputs to distal dendrites of CA1 pyramidal neurons. Cell 119(5):719–732PubMedGoogle Scholar