I used to get into these weird states in college, and coffee consumption certainly triggered it. Things would get so bad that I was having trouble piecing together the meaning of sentences I read. I knew what all the words meant, but it was like I couldn't even put them together into a whole with a meaning. I imagine if anyone is like that all the time it must be pretty awful. It's generally environmentally triggered, though. Clean up the environment, and it won't be happening.