A neurologist observes that a patient with multiple sclerosis has slower nerve conduction velocity. Which mechanism explains this phenomenon within myelinated neurons?

💡 Explanation

Demyelination in multiple sclerosis impairs action potential propagation, disrupting saltatory conduction along axons because myelin sheaths normally insulate the axon and increase conduction velocity; therefore, nerve impulses jump between Nodes of Ranvier, rather than propagating continuously. The others don't explain the slowing.

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