At any one moment. We are being bombarded by sensory information
Our brains do a remarkable job of making sense of it all
It seems easy enough to separate the sounds we hear from the sights we see
but there is one illusion that reveals this isn't always the case
Have a look at this ah what do you hear ba ba, Ba?
But look what happens when we change the picture
and yet, the sound hasn't changed in
Every clip you are only ever hearing ba with a b
it's an illusion known as the mcGurk effect Ba take another look
Concentrate first on the right of the screen now to the left of the screen
The illusion occurs because what you are seeing clashes with what you are hearing.
In the illusion, what we see overrides what we hear so the mouth movements
We see as we look at a face can actually influence what we believe we're hearing if we close our eyes
We actually hear the sound as it is if we open our eyes. We actually see how the mouth movements can influence what we're hearing
It's a bizarre effect
Remember the only sound you're hearing is ba with a b
what's remarkable about this illusion is even knowing how it's done
Doesn't seem to make a difference
The effect works no matter how much you know about the effect. I've been studying the McGurk Effect for 25 years now.
And I've been the face in the stimuli I've seen stimuli thousands of thousands of times, but the effect still works on me.
I can't help it. The speech brain just takes in that information, it doesn't care about what outside knowledge you bring to bear.
The McGurk Effect shows us that what we hear may, not always be the truth.
But it also helps us to understand what happens when our senses conflict.
When the brain has the conflicting information, it tries to make sense of that conflict and
depending on what type of
modality is providing more, I guess, salient information, that information might override or at least combine with the other information.
So we can't always trust what we hear because sometimes our sense of vision takes over,
enabling us to maintain a coherent view of the world.
