Some of you will see a duck, others a rabbit - but not both at once. The image itself allows

for both interpretations and switching between them involves some mental effort.

And when you look at the duck, for example, do you see the same duck that I see? When

you and me both see the colour orange, do we experience the same hue? Or the same illusion?

Research suggests the differences in our subjective experiences are tied to the different sizes

of certain areas in our brain.

In one study, researchers asked participants to judge which of these circles is larger.

Even though you know these two circles are the same size, it’s almost impossible to

see it that way.

Using fMRI, they mapped the participants’ visual cortex, the part of your brain responsible

for processing visual information.

They found those with a larger visual cortex were better at judging the true size of the

inner circle, and those with a smaller visual cortex were the least accurate. And they came

to the same conclusion using other illusions.

It’s difficult to say why exactly the size of one brain area leads to people being more

easily tricked by optical illusions.

It could have to do with the concentration of chemical messengers inside the visual cortex.

Other studies have found that the magnitude of optical illusions differs in people with

autism or in people from different cultures.

Things we see can be constructed in many different ways. When children were shown the duck-rabbit

illusion on Easter Sunday (rabbit season), more children see the rabbit, where on other

Sundays they are more likely to see the duck (duck season).

In late November, you might even view the duck through the lens of turkey season.

Sure, What You See Is What You Get, but remember that things may be perceived through different

lenses.

Like the size of these circles, the length of these lines, or a pod of dolphins splashing

the hours away.

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