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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Subthreshold dynamics of a single neuron from a Hamiltonian perspective.
1Department of Engineering, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand. m.wilson@waikato.ac.nz
Summary
Action potentials in cortical neurons are driven by a drop in inhibition, leading to exponential increases in conjugate momenta. This Hamiltonian model reveals how noise dynamics propel neurons toward firing.
Area of Science:
- Computational neuroscience
- Classical mechanics
- Neuronal dynamics
Background:
- Cortical neuron action potentials are fundamental to neural computation.
- Understanding the precise biophysical mechanisms leading to action potentials is crucial.
Purpose of the Study:
- To investigate the behavior of a modeled cortical neuron approaching an action potential using classical mechanics.
- To elucidate the role of noise and inhibition in neuronal firing.
Main Methods:
- Derivation of Hamilton's equations from a two-component dynamic neuron model (Wilson model).
- Incorporation of noise inputs into the system dynamics.
- Theoretical analysis and computational simulations.
Main Results:
- Conjugate momenta are identified as linear combinations of noise inputs.
- Neuronal firing is linked to a decrease in inhibition caused by increased negative bias in noise.
- Simulations show an exponential increase in noise bias preceding an action potential.
Conclusions:
- Action potentials arise from the exponential growth of conjugate momenta, driven by noise.
- The Hamiltonian framework provides a novel perspective on neuronal excitability and nonlinear dynamics.
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