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The McGurk Effect: When Your Eyes Trick Your Ears


Here's a psychological illusion that was new to me: The McGurk Effect. It occurs when someone's lip movements don't match up with what they're actually saying. The result is that the same audio can sound completely different depending on what your eyes see.

This BBC video demonstrates it pretty dramatically:

The effect reminds me our test Double Trouble, and what is known as the Stroop Effect. In that test, your brain automatically processes the meaning of a word, even when you don't want it to, just like your brain automatically processes lip movements even when they're wrong.

It makes me wonder if there is anyone out there who the McGurk effect does not work on, and if the same people would be better at Double Trouble. There is some evidence that people who can see both sides of an illusion are more creative, possibly because strong executive functioning helps with both creativity and interpreting ambiguous stimuli. It's even more more reason to keep your brain functioning at its best.

Do you experience the effect? Let me know in the comments below.

This post was written by Mike Battista, a staff scientist at Cambridge Brain Sciences.