Rochelle developed multiple sclerosis when she was 27. After eight years she had lost a good portion of her ability to control her skeletal muscles. How did this happen?

Video transcript

Hi, everyone. Welcome back. Let's look at the next question. It says, which of the following best describes the effect of multiple sclerosis on neurons. Choice. A demyelination of neurons B, thickening of axons, C, increased neuronal firing or d enhanced neuronal communication. Well, we can recall from our content video that multiple sclerosis causes the destruction of the myelin sheath with the formation of scar tissue. That's where the word sclerosis comes in because the myelin chief acts as the insulator for those electrical signals traveling through the neuron. The fact that the myelin sheath gets destroyed and scar tissue gets formed interferes with the normal conduction of those nerve signals. This means it has a wide number of symptoms including muscle weakness, numbness, vision problems. So to describe the effect of multiple sclerosis on the neurons, we'd want choice. A, the demyelination of neurons. It doesn't cause the other choices here. It doesn't cause thickening of axons, which is Choice B and it interferes with the conductance of the electrical signal. So it does not cause increased neuronal firing or enhanced neuronal communication. So neither of those is the correct answer. So again, choice, A demyelination of neurons is the best description of the effect of multiple sclerosis. See you in the next video.