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Induction of an Isoelectric Brain State to Investigate the Impact of Endogenous Synaptic Activity on Neuronal Excitability In Vivo
Published on: March 31, 2016
A cellular mechanism for graded persistent activity in a model neuron and its implications in working memory
Jun-Nosuke Teramae1, Tomoki Fukai
1Brain Science Research Center, Tamagawa University, machida, Tokyo, 194 8610, Japan.
Journal of Computational Neuroscience
|March 25, 2005
Summary
This study proposes a new cellular mechanism for working memory, explaining how single neurons achieve persistent firing. It involves bistable inositol 1,4,5-trisphosphate (IP3) and Ca2+ dynamics for graded neuronal activity.
Area of Science:
- Neuroscience
- Computational Neuroscience
- Cellular Signaling
Background:
- Working memory relies on persistent neuronal firing, traditionally attributed to synaptic reverberation.
- Recent findings suggest single neurons can exhibit persistent firing, challenging existing models.
Purpose of the Study:
- To propose a novel cellular mechanism for generating persistent firing across multiple firing rates in single neurons.
- To explain how intracellular signaling can underlie working memory functions.
Main Methods:
- Computational modeling of neuronal activity.
- Simulating inositol 1,4,5-trisphosphate (IP3) and Ca2+ dynamics within subcellular domains.
- Investigating firing rate-dependent switching of bistable intracellular elements.
Main Results:
- A model demonstrating bistable inositol 1,4,5-trisphosphate (IP3) and Ca2+ concentrations.
- Successful generation of graded persistent firing in simulated rat entorhinal neurons.
- Proposed mechanism shows firing rate-dependent switching of intracellular signaling cascades.
Conclusions:
- A cellular mechanism involving bistable IP3 and Ca2+ dynamics can explain persistent neuronal firing.
- This intracellular mechanism provides a basis for working memory at the single-neuron level.
- The proposed model is extendable to various intracellular Ca2+ signaling pathways.
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