What distinguishes why an action potential propagates unidirectionally down an axon, rather than bidirectionally from the axon hillock during neuronal signaling?

💡 Explanation

Unidirectional propagation happens because of the absolute refractory period. Sodium channels that have just opened and inactivated proximally, remain inactivated, preventing immediate reactivation and reverse propagation; therefore, the action potential moves forward rather than backwards, ensuring signal directionality, rather than bidirectional travel.

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