How does the McGurk effect trick your brain?

Name: How does the McGurk effect trick your brain?
Uploaded: 2023-09-14T01:50:04.149Z
Duration: 1 min 31 s
Description: The McGurk effect illustrates how visual cues can have an impact on our perception of speech.

The McGurk effect illustrates how visual cues can have an impact on our perception of speech.

Encyclopædia Britannica, Inc.

Encyclopædia Britannica, Inc.

Worried about diphtheria? No? Thank vaccines.

How We Develop New Vaccines
Frans Hofmeester (A Britannica Publishing Partner)

Time-lapse video, by Dutch photographer Frans Hofmeester, of his daughter from birth to age 12.

View Frans Hofmeester's photography of his daughter from birth to age 12
Encyclopædia Britannica, Inc.

The AIDS epidemic began in the late 20th century, at a time when fewer people were dying from other infectious diseases than in earlier periods of history.

How HIV and AIDS Redefined the Fight Against Infectious Diseases
© Behind the News (A Britannica Publishing Partner)

Learn about Henry Molaison (better known as “patient H.M.”), whose short-term memory loss following a lobotomy helped researchers to understand how brain structures are related to brain function.

Patient H.M. and short-term memory loss explained
© World Science Festival (A Britannica Publishing Partner)

A discussion of the unique features of Albert Einstein's brain.

Hear a discussion about the unique physical structure of Albert Einstein's brain
Contunico © ZDF Studios GmbH, Mainz

Learn how the brain processes language.

How does the human brain process language?
© MinuteEarth (A Britannica Publishing Partner)

Learn about the brain and how studies of brain disorders—such as aphasia caused by damage to the Broca area—have helped advance the scientific understanding of cognition.

Know Broca's lesion method in mapping brain activity in humans and how studies of brain disorders to the Broca area help evolve the scientific understanding of cognition

News •

Novel treatment clears dementia-linked proteins from the waking brain • Nov. 4, 2026, 12:31 PM ET (News-Medical)

Could consciousness begin deep in the brain? Researchers make the case • Nov. 2, 2026, 10:20 AM ET (Medical Xpress)

Scientists discover a hidden messaging system deep inside the brain • Oct. 23, 2026, 4:30 AM ET (Science Daily)

Alzheimer’s Researchers Look at an Unusual Data Point: Head Shape • Oct. 22, 2026, 5:00 AM ET (New York Times)

Scientists are growing human brain tissue in living mice—could this make their welfare harder to assess? • Oct. 19, 2026, 4:40 PM ET (Phys.org)

Transcript

[MUSIC PLAYING] SPEAKER 1: Baa.

SPEAKER 2: Watch this video.

SPEAKER 1: Baa. Baa.

SPEAKER 2: What sound is the person making?

SPEAKER 1: Baa. Baa. Baa. Baa. Baa. Baa. Baa.

SPEAKER 2: Did the sound change?

SPEAKER 1: Baa. Baa.

SPEAKER 2: Now close your eyes.

SPEAKER 1: Baa. Baa. Baa. Baa.

SPEAKER 2: Did it change again?

SPEAKER 1: Baa.

SPEAKER 2: This is called the McGurk effect. It's an illusion that shows how visual cues can have an impact on our perception of speech. In these clips, the speaker is only saying baa.

SPEAKER 1: Baa.

SPEAKER 2: But when you see his mouth make the sound, fa, you hear that instead, even though the sound he's making hasn't changed. If you focus on the left side of the screen, you probably hear baa.

SPEAKER 1: Baa.

SPEAKER 2: If you focus on the right side, you probably hear fa. But the only sound playing is baa.

SPEAKER 1: Baa.

SPEAKER 2: The McGurk effect explains this phenomenon. The visual information you receive by watching the mouth move affects your perception of the auditory information you receive by listening to the sound. Let's play it again.

SPEAKER 1: Baa. Baa. Baa. Baa. Baa. Baa.

SPEAKER 2: Are you experiencing the McGurk effect?

SPEAKER 1: Baa.

Last Modification: Nov. 10, 2026