A full 30 second block out

I've experienced long meetings with my mind wandering away from time to time but yesterday was a first for me. I was in a meeting, and this other manager kept on talking on and on and on. My mind just went blank. It was as if a full 30 seconds had been cut off my life without me knowing about it. But even more amazingly was when he called out my name and was asking me for something, I gave an instant reply. I knew what the question was. Very odd. I wonder if these things happen to everybody from time to time....