Why does autoimmune demyelination in nervous tissue lead to slower action potential propagation?

💡 Explanation

Demyelination reduces the insulation around nerve fibers, thus it impairs the saltatory conduction mechanism. Action potentials must then propagate continuously along the axon rather than 'jumping' between Nodes of Ranvier, because conduction velocity decreases. Therefore, demyelination leads to slower propagation rather than faster transmission.

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