You can distract me extremely easily if I don't have any interest in what I'm doing. And vice versa. Try talking to me when I'm reading an amazing book, you're sure to be ignored - even without my earphones plugged in. You're also bound to fail to distract me when I just turn the volume of my headphones up and shove out the rest of the world. XD Oh, and when I'm studying really hard, it's difficult to steal my attention as well.