Ion concentration dynamics as a mechanism for neuronal bursting
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We describe a simple conductance-based model neuron that includes intra- and extracellular ion concentration dynamics and show that this model exhibits periodic bursting. The bursting arises as the fast-spiking behavior of the neuron is modulated by the slow oscillatory behavior in the ion concentration variables and vice versa. By separating these time scales and studying the bifurcation structure of the neuron, we catalog several qualitatively different bursting profiles that are strikingly similar to those seen in experimental preparations. Our work suggests that ion concentration dynamics may play an important role in modulating neuronal excitability in real biological systems.
KeywordsNeuron Potassium Sodium Ion concentration Burst Seizure Epilepsy
The authors would like to acknowledge the assistance of Jeremy Owen in creating Fig. 2. This work was supported by the Collaborative Research in Computational Neuroscience program at National Institutes of Health via grant R01-MH79502 (EB).
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