who knew this existed ? (spoiler, kind of)
not me.
acc to wikipedia, steve woz and jane goodall have it.
Several years ago I read a mystery novel that centered around it, and then not long after saw a segment on 60 Minutes. They interviewed several people who have it; the one that made the most impact on me was the woman who talked about not recognizing her children. It was heartbreaking.
There's someone in my head but it's not me.