Identity?

You have to read this article in the NY TImes about Hannah Emily Upp, a young woman who went out jogging and suffered from a rare form of amnesia called  dissociative fugue (the name alone is intriguing!) which manifests as spontaneous travel and a loss of the memory of one's own identity. Bizarre.  

Here is the money quote:
“We tend to experience our identity as a thing, as if it’s a constant,” added Dr. Loewenstein... “But it’s a lot less stable and has less unity than we want to believe.”