What is "Fibro Fog?"

If you are familiar with fibromyalgia, you might be familiar with what we call "Fibro Fog." When someone asks me a question, my mind goes completely blank, other than knowing that I know the answer to the question. Some of the things I've done during particularly "foggy" days were putting my watch on the wrong arm and putting my watch on upside down. That is just a couple that come to mind today! I never know what tomorrow might bring!