Did I hear that right?

Steps to understand the McGurk effect:

1. watch this video. Ask yourself if you heard that right? Chances are you didn't.
   
2. play this video again with your eyes shut
   
3. say "holy shit."
   

The McGurk effect highlights the combination of both auditory and visual cues in speech recognition. This clip was produced by overlaying the sound of "ba" over a video of someone saying "ga." The perceived speech should sound like a combination somewhere between the two: "da." If you close your eyes, there is no incorrectly matched video to confuse your brain and only the spoken "ba" can be heard. Cool, no?