relative refractory period

biology

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July 13, 2026

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The relative refractory period in biology is a phase following a nerve or muscle response during which a second response can be generated, but only with a stronger stimulus than initially required. This period occurs after repolarization, when the cell membrane returns to its polarized state, with the inside negative relative to the outside. It follows the absolute refractory period, where no second action potential can be initiated regardless of stimulus strength. This mechanism is crucial for the proper transmission of nerve impulses.1

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nervous system
Repolarization
…it is followed by a relative refractory period, during which another action potential can be generated, but only by a greater stimulus current than that originally needed. This period is followed by the return of the neuronal properties to the threshold levels originally required for the initiation of action potentials.
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…it is followed by a relative refractory period, during which another action potential can be generated, but only by a greater stimulus current than that originally needed. This period is followed by the return of the neuronal properties to the threshold levels originally required for the initiation of action potentials.
Read More