This is the weirdest thing I've heard of in months. A science program recently had this demonstration - they play 3 videos of a person saying a word, and you're supposed to guess what consonant the word starts with. This is VERY weird, I warn you. What they did, was play the SOUND of one word, and the VIDEO of a person saying a different word. You will hear a different sound - if they play a video of a person saying a different sound. Yep. If you SEE a person's mouth making one sound, and hear a different sound, you will actually perceive a 'wrong' sound.