Physiology Introduction to Central Nervous System 7abb56d5 Slow conduction velocity is seen with which of the following nerve fibers? A Preganglionic autonomic nerve fibers B Postganglionic autonomic nerve fibers C Motor nerves D Sympathetic nerve fibers High-Yield Explanation Slow conduction velocity is seen in 'C'- fibers because they are unmyelinated. These are post ganglionic sympathetic nerve fibers.