In addition to C nerve fibers, which nerve fibers carry pain impulses?

In addition to C nerve fibers, which nerve fibers carry pain impulses?

• A. A Alpha
• B. A Beta
• C. A Gamma
• D. A Delta

Answer: (D)

Pain signals come through different nerve fiber types. C fibers are unmyelinated and carry slow, dull, poorly localized pain. In addition to them, the fast component of pain is carried by A-delta fibers, which are thinly myelinated and conduct impulses more quickly. This results in a sharp, well-localized sensation at the moment of injury—the first pain. A-delta fibers respond to noxious mechanical and thermal stimuli and project to the dorsal horn to relay those signals. The other fiber types listed—A-alpha and A-beta (large myelinated fibers for motion and touch) and A-gamma (motor fibers to muscle spindles)—do not primarily carry nociceptive (pain) signals.

Pain signals come through different nerve fiber types. C fibers are unmyelinated and carry slow, dull, poorly localized pain. In addition to them, the fast component of pain is carried by A-delta fibers, which are thinly myelinated and conduct impulses more quickly. This results in a sharp, well-localized sensation at the moment of injury—the first pain. A-delta fibers respond to noxious mechanical and thermal stimuli and project to the dorsal horn to relay those signals. The other fiber types listed—A-alpha and A-beta (large myelinated fibers for motion and touch) and A-gamma (motor fibers to muscle spindles)—do not primarily carry nociceptive (pain) signals.