What is the correct order of nerve fiber types from fastest to slowest?

The correct order of nerve fiber types from fastest to slowest is Alpha, Beta, Delta, C. This classification is based on the diameter of the nerve fibers and their myelination.

Alpha fibers are the largest and most heavily myelinated, which allows them to conduct impulses the fastest. They play a significant role in motor functions and proprioception, effectively transmitting signals rapidly.

Beta fibers are slightly smaller than alpha fibers but are still myelinated, enabling relatively quick transmission of sensory signals related to touch and pressure. Although they are not as fast as alpha fibers, they still convey information more swiftly than the smaller types.

Delta fibers, while also myelinated, are thinner than both alpha and beta fibers. They are responsible for transmitting sharp pain and temperature sensations and are slower than the previous two types.

C fibers are the smallest and unmyelinated, resulting in the slowest transmission speed. They are primarily involved in transmitting dull, aching pain and are associated with chronic pain sensations.

Understanding the differences in diameter and myelination among these fiber types helps clarify why Alpha, Beta, Delta, and C are arranged in this specific order regarding impulse conduction velocity.