Motor neuron disease is at anterior horn cell, pyramidal neurons and not the nerves. Thus the conduction velocity in the nerves is normal. Leprosy - Affects nerves and both sensory nerve conduction /motor nerve conduction studies may demonstrate reduced amplitude in affected nerves but occasionally may reveal demyelinating features. Charcot-Marie-Tooth disease (CMT) -MC hereditary neuropathy and has reduced motor nerve conduction velocity A.I.D.P -Segmental demyelination in the spinal cord and peripheral nerves. Early features-prolonged F-wave latencies Prolonged distal latencies Reduced amplitudes of compound muscle action potentials, d/t involvements of nerve roots and distal motor nerve terminals