During the thirty years or more that I have taught writing skills, one of the hardest concepts to get across to students is the idea that learning to speak a language and write a language are two different things. Here is a variation on that same thing - the case of a man who suddenly lost the ability to read, but who could still write. Fascinating stuff. I can see a chapter in Oliver Sacks next book already.
UPDATE: Blimey! On the same day that I posted this, the New Yorker comes out with exactly what I predicted. Read it here >>