The McGurk Effect – Watch Your Ears Lie To You

The McGurk effect is a perceptual phenomenon which demonstrates an interaction between hearing and vision in speech perception. It suggests that speech perception is multimodal, that is, that it involves information from more than one sensory modality. The McGurk effect is sometimes called the McGurk-MacDonald effect. It was first described in a paper by Harry McGurk and John MacDonald in 1976. (source – Wiki)

The McGurk effect is a compelling demonstration of how we all use visual speech information. The illusion shows that we can’t help but integrate visual speech into what we ‘hear’. So like with our article on Digital Deception, you can’t always believe what you see and in this case hear as well.

No matter how much you understand the McGurk effect, it makes little difference to the outcome, you can watch the below clip as many times as you want, but the outcome will remain the same.

Watch the McGurk effect below – 3:26 mins

The above clip came from a very interesting BBC2 program called “Horizon: Is Seeing Believing?” This program can be watched in full below.

HORIZON explores the strange and wonderful world of illusions, revealing the tricks they play on our senses and why they fool us.

Horizon shows how easy it is to trick your sense of taste by changing the appearance of food and drinks, explains how what you see can change what you hear, and reveals just how unreliable our sense of colour can be.

And neuroscientist Dr Beau Lotto carries out an illusion involving a chair and a volunteer.

All this trickery has a purpose.

It is helping scientists to create a new understanding of how our senses work – not individually, but connected together.

It holds the intriguing possibility that one sense could be mapped into another.

This is what happened to 41-year-old American Daniel Kish, who lost his sight as a child.

He is now able to create a vision of the world by clicking his tongue, which allows him to echo-locate like a bat.

Using the medium of sound to detect obstacles, Daniel has made a name for himself as a teacher of this method of orientation to blind people.

Scientists now believe that Daniel’s brain has actually rewired itself, enabling him to use sound to create a visual image of the world.

BBC Documentary – Horizon 2010 – Is Seeing Believing in HD- 59 minutes