Hey!  I was talking to you

Ever have to walk over to your kid and tap him on the shoulder to get his attention? "I called you like seven times!" you say. He says with doe-like eyes as he puts down the x-box controller "But I didn't hear you!"

He's actually sort of right. His ears heard but his mind was a thousand light years away... He was in trance! It's normal and natural. He was not ignoring you. His attention was fixated elsewhere.