The McGurk effect

This is old news, but I just learned about it tonight...

Scientific American writes:

If we watch a video of a person mouthing the word "ga," but have a synced voice-over of that person saying "ba," what we end up hearing, is a third variation that's never been said! That word is "da".

And even though you now know it's an illusion—you will still, when you see the video, think you are hearing "da". But if you close your eyes, and do not see the person's lips forming the word "ga," you'll hear what they are actually saying, which is "ba".

And here's the video.



Strange...

I bet if you gave listeners a fake "transcript" of the audio that said "da da" (instead of the video) they'd hear it as "da da" then too.