Those of us with CFS all get these "brain fog" moments: when it feels like half of our brain has gone offline, and we find ourselves struggling with cognitive dysfunction for hours, or sometimes days, or longer. Disastrous or perplexing though these brain fog moments can be, a few hours afterwards, when we have recovered back some of our mental faculties, they can seem quite funny in retrospect or sometimes quite disconcerting, depending on the circumstances. One brain fog story I heard was about a CFS patient going out to mail a letter, and instead of locating a mailbox, she tried to post it in a parking meter, and just could not figure out why her efforts were not working! Another brain fog story I read (on this site) was this: "the brain fog was so bad I didn't recognize a number 8 on a page. I couldn't figure out why those 2 circles were on top of each other!" These are very interesting stories. We have all been there, totally perplexed over a simple task or totally confused in trying to understand something fundamental and basic. It really seems as if part of the brain does go offline during these brain fog moments: like as if you temporarily loose internal communication with certain "brain areas": like your object recognition faculty, or your logic faculty, or your long-term memory faculty. I think more research should be done on this CFS brain fog phenomenon. It is very intriguing in itself, and trying to understand it better should yield some clues as to what is going on in the brain in CFS. Anyway, it would be good to hear everyones' stories of their best "brain fog moments".