What type of nerve fibers are typically responsible for slow signals in the nervous system?

The type of nerve fibers that are typically responsible for slow signals in the nervous system are unmyelinated fibers. These fibers lack the myelin sheath that serves to insulate and speed up signal transmission in myelinated fibers. In unmyelinated fibers, the action potential propagates more slowly because the electrical impulses must travel continuously along the entire length of the membrane rather than jumping between the nodes of Ranvier, as is the case with myelinated fibers. This continuous conduction process results in a slower overall signal conduction velocity.

Unmyelinated fibers are often found in autonomic pathways and are associated with the transmission of pain and temperature sensations, as they need to convey signals that require more sustained but slower responses. In contrast, thicker myelinated fibers facilitate rapid conduction of signals, such as those involved in reflexes and motor control. This difference in structure directly correlates with the speed of signal transmission, making unmyelinated fibers the slowest among the various types of nerve fibers.