Hodgkin–Huxley Action Potential
The Hodgkin–Huxley model describes excitable biological membranes with voltage-dependent sodium and potassium conductances controlled by gating variables (m, h, n). A depolarizing current raises V; once sodium channels open, positive feedback drives the upstroke, after which potassium repolarizes the cell. This page integrates the classical squid-axon parameter set with RK4 and plots membrane voltage together with effective conductances.
Who it's for: Undergraduates in biophysics or neuroscience learning action potentials beyond integrate-and-fire cartoons.
Key terms
- Hodgkin–Huxley
- Action potential
- Sodium channel
- Potassium channel
- Gating
- RK4
RK4 on the HH ODEs; pulse starts at 1 ms. Increase I or pulse width to cross threshold and fire.
Live graphs
How it works
Numerical integration of the Hodgkin–Huxley excitable membrane: sodium activation/inactivation and potassium activation produce the stereotyped spike; conductance traces show channel gating.
Frequently asked questions
- Why two graphs for voltage and conductances?
- V spans tens of millivolts while g_Na m³h and g_K n⁴ peak on a different scale; overlaying them on one autoscaling axis would hide one of the traces.
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