I think it would help you to read as much as you can about the disease. Once you understand what the physiological effects are -- what the damage that is actually going on is, you will be better able to know why your body may be doing the things it does. There are some good websites, from the various ms societies, who can also provide you with more information.
Memory, vision, etc. Can all be affected by the damage to nerves. But since the disease is so variable, it's also easy to blame anything that's happening on it -- so if you understand it better, you'll know if maybe there is anything to do, or your symptoms might be down to something else.