The conduction deficit depends on the extent of demyelination and remyelination. Demyelination may stop or slow down conduction. More important, it may prevent the conduction of a train of impulses. Axonal information is often coded in bursts of action potentials. Demyelinated axons may be able to support one impulse but not a rapid train of impulses.
Demyelination can also reduce the safety factor of conduction.
In other words, an impulse has a smaller chance of getting through a demyelinated zone. Demyelination or abnormal myelination reduces the amount of information that an axon can pass through. The part of the spinal cord that is situated at the bony segmental level of L1 contains most of the spinal cord that represent the L1-S4 spinal segments. These segments innervate the pelvic area and the legs. Collections of neurons in these segments control a variety of functions.