"Reality Snap" - In The Knerd

I have this thing that happens to me whenever I get really into what I'm doing, and I dub this strange feeling "reality snap". Basically, this happens the most when I'm reading a really interesting book, or I go see a movie in the theaters. When I finish doing said activity, I get this weird groggy feeling and start getting a headache. The only reasonable explanation for this is that when I'm getting really into the book/movie, I zone out, focusing on the book and ignoring everything else. Then, when I "snap" back into reality, the sudden rush of information to my brain from recognizing my surroundings again just overwhelms me.

Or maybe I'm just crazy.

Anyways, does anyone else experience this? Is there an actual name for this?

I'll have to do some dig......oh never mind, finally got through the queue to play World of Warcraft, so now it's time to work on getting my death knight to 82!!