A demyelinating disease slows action potential propagation. Which consequence results within affected neurons, specifically regarding spatial summation at the axon hillock?

💡 Explanation

Demyelination reduces the speed and efficiency of action potential propagation along the axon. Because spatial summation relies on near-simultaneous arrival of graded potentials, slower propagation diminishes the impact of excitatory postsynaptic potentials at the axon hillock; therefore, the effect is reduced, rather than alternative outcomes related to inhibitory signals or firing threshold changes.

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