Decreased nerve conduction velocity Decreased motor nerve conduction velocity Reduced motor nerve conduction velocity HP:0003431 HP:0000760 Decreased motor NCV UMLS:C1858729 HP:0003379 HP:0003395 Newborn infants have values that are approximately half that of adults, and adult values are normally reached by age 3 or 4. Motor nerve conduction is evaluated by recording the compound muscle action potential (CMAP) associated with a mechanical contraction of a given muscle in response to electrical stimulation of the motor nerve fibers supplying that muscle. The CMAP is the sum of all the action potentials occurring individually in the contracting muscle fibers. HP:0006907 A type of decreased nerve conduction velocity that affects the motor neuron. Decreased motor nerve conduction velocities HP:0003437 HP:0008170 Abnormal motor nerve conduction velocity