McGurk effect

As McGurk effect is known to influence the perception of an acoustic speech signal by the simultaneous observation of a lip movement or unconscious lip-reading. These audio- visual deception is considered a milestone in the psychology of perception, and as evidence of the integration of visual impressions in speech perception.

Effect

In the classical experimental set-up of a subject of a video tape is played on which a person is to see who pronounce the syllables / ga -ga /. The sound track of the video tape, however, was manipulated and lets the syllables / ba-ba / hear the volunteers. Approximately 98 percent of adult subjects indicate that they have the syllables / da -da / perceived.

Explanation

After the motor theory of speech perception our brain tries to use all signals including the optical information, to open up, as the acoustic signal has been generated. Since our memory is that there is a direct correlation between lip movement and sounds, practicing visual information of lip movement from a great influence on the processing unit for phonemes in our brain. The Language Centre apparently combines the contradictory sensory impressions in order to correct them, and thus creates a new virtual impression.

History

The mid-1970s discovered the developmental psychologist Harry McGurk and his colleagues at the University of Surrey in Guildford the effect by accident while they investigated the perception in infants.

By publishing the results in Nature (1976) and the high attention related have conducted numerous trials similar pattern: The effect was examined in different languages ​​, some studies looked at the effect on children, others have examined whether similar results occur in non-linguistic sound signals.

In languages ​​such as Mandarin Chinese and Japanese, however, a reduction of the effect was found.