A demyelinating disease slows action potential propagation along a neuron. Which effect dominates as the internodal distance increases in these neurons?

💡 Explanation

As internodal distance increases with demyelination, the action potential decays more before reaching the next node because the myelin sheath, normally providing insulation, is damaged. Therefore, temporal summation failure risk increases, rather than enhanced signal propagation, because signal strength diminishes below the threshold required for triggering an action potential.

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