How does myelin affect signal transmission in neurons?

Myelin significantly enhances the speed of signal transmission in neurons. This specialized insulating layer wraps around the axons of many neurons, creating discrete segments along the length of the axon. The presence of myelin allows for a process known as saltatory conduction, where the electrical impulses jump from one node of Ranvier (the gaps in the myelin sheath) to another.

This jumping mechanism is much quicker than the continuous wave of depolarization that would occur in unmyelinated axons. Myelinated neurons can transmit signals at speeds of up to 120 meters per second, significantly faster than unmyelinated neurons, which might transmit signals at speeds closer to 1 meter per second. This rapid transmission is essential for efficient communication within the nervous system, enabling quick reflexes and coordinated responses.