Question

How does the diameter of a nerve affect the conduction velocity? Explain why this is the case.

Answer 1

Larger diameter axons have a higher conduction velocity, which means they are able to send signals faster. This is because there is less resistance facing the ion flow. Increasing fiber diameter increases nerve conduction velocity. ... increasing inward current by increasing the axon diameter (larger axon, larger membrane area, more ion channels) and increasing myelination (more myelin more ion channels are concentrated in the nodes of Ranvier) increases nerve conduction velocity.

Mean fiber diameter (axon plus myelin sheath) also increased with time after nerve transection. Recovery of mean fiber diameter was well correlated with MCV, even though regenerating nerves likely contained many small nonconducting fibers.