How does Multiple Sclerosis primarily affect the nervous system?

Multiple Sclerosis (MS) primarily affects the nervous system by damaging the myelin sheaths that surround and protect nerve fibers. Myelin is a crucial insulating layer that allows for the efficient transmission of electrical signals along the nerves. In MS, the immune system mistakenly attacks the myelin, leading to demyelination. This process results in impaired communication between the brain and other parts of the body, as the nerves can no longer transmit signals effectively.

The damage to myelin can lead to various neurological symptoms, such as weakness, numbness, balance issues, and cognitive dysfunction. The loss of myelin can also create areas of scar tissue—known as sclerosis—which is where the name "Multiple Sclerosis" originates. As the disease progresses, the extent of myelin damage can vary, leading to different patterns of symptoms among individuals.

The other choices do not accurately represent the primary mechanism of MS. For example, promoting nerve regeneration does not occur in MS as a primary effect; in fact, the disease often hinders regeneration. Increasing neurotransmitter production is not a direct effect of MS; rather, the dysfunction and damage to the nerves can sometimes lead to disrupted neurotransmitter signaling. Lastly, while overactivity of the nervous system can occur in some conditions,