Which type of receptor has an intermediate conduction velocity?

• A. Proprioceptors
• B. Nociceptors
• C. Mechanoreceptors
• D. Thermoreceptors

Answer: (C)

Conduction velocity of sensory signals depends on the fiber type that carries the information. Proprioceptors use the largest, heavily myelinated fibers, so their signals travel the fastest. Mechanoreceptors connect to large, myelinated fibers too, but not as large or as specialized as those for proprioception, placing their conduction velocity in the middle range. Nociceptors and many thermoreceptors are carried by smaller or less myelinated fibers (such as A-delta and C fibers), which conduct more slowly. So, mechanoreceptors end up with an intermediate conduction velocity, faster than pain and some temperature signals but slower than proprioceptive signals.