Hope this is new to people, the McGurk Effect is a auditory illusion where seeing the person lips and not seeing them affects what we hear as demonstrated here on this website: http://www.media.uio.no/personer/arntm/McGurk_english.html You'll need Quicktime and before playing the short clip read the note beneath it. Its a facinating effect. Read below after watching the short clip. Some people hear Da da da da no matter what, some hear ba ba ba ba no matter. Some actually hear combination of those two. It differs from person to person. A normal person should hear ba ba ba when covering the lips and da da da when not. I'm normal. You?