. There are many diseases that affect signal transmission along neural pathways. These includemultiple sclerosis (MS), myasthenia gravis, and amyotrophic lateral sclerosis (ALS or 'LouGehrig's Disease). Often, a component of these afflictions is a malformation or degenerationof the myelin sheath. MS is a demyelinating disease, which means that the axons of neuronsare intact but the myelin sheaths are damaged. Why would loss or damage to the myelinsheath be a problem for signal transmission, even if the axon was intact

In neurons that are enveloped by myelin sheath, the nerve stimulus or neuronal action potential is transmitted in a saltatory way, that is, this action potential jumps in the spaces not surrounded by the myelin sheath and it is in this way that it is transmits much more efficient and faster.

Explanation:

Myelin neurons are those that are covered by myelin sheaths, this sheath is formed mainly by fatty acids, these fatty acids generate an alternate isolation along the axon so that the stimulus diffuses through the bare areas where they will have ionic channels premises in order to generate the potential for action.

If this myelin sheath disappears, not only is the response slower, but it is rendered incapable because an axon that does not have ion channels to spread the signal is discovered in the external environment.

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