Holy crap, this is funny.
• Someone says Senator Kit Bond fell asleep during an intelligence briefing.
• Bond denies it, yad yada.
• Someone asks Senator Orrin Hatch about it. He says that the lights in the briefing room are so bright that sometimes “you have to rest your eyes for a bit; you get light burn.”
You get "light burn." On your eyes. So you have to close them sometimes. Which is why people can think you're sleeping.