AN optical illusion tricks the brain into seeing a bright white glow — but researchers say it could be due to an evolutionary boost.
The confusing vision shows how your eyes can lie to you.
The image shows what Akiyoshi Kitaoka calls the “Asahi” illusion of brightness.
The image shows yellow-to-black gradient petals surrounding a white center.
But the middle part appears lighter than the white background, although it has the same hue throughout the image.
There is a scientific explanation for the illusion.
According to the journal Frontiers in Human Neuroscience, the reason for the eye trick is that central light patterns of different colors (e.g. green, magenta, but also white) suggest light expansion.
And the reason the eyes are fooled might actually be because our brains evolved to avoid sudden bright light.
Researchers found that the Asahi illusion caused people’s pupils to constrict, similar to when an eye gazes into bright sunlight.
The researchers write: “Preliminary confinement to apparent light may serve an important function by promoting behaviors not to be ‘blinded’ by physical (real) light.”
Brightness illusions like Asahi have a geometric resemblance to the gradients of color formed by the glare of strong sunlight when partially blocked by plant foliage or cloud formations.
The pupils of the eye subconsciously adapt to the ambient light.
They widen in the dark to capture more light and narrow in the light to protect the eye from overexposure.
“There is no reason per se that the student in this situation should change because nothing is changing in the world,” Bruno Laeng, a psychology professor at the University of Oslo and author of the study, told the New York Times.
“But something has definitely changed in the mind,” he said.
The researchers believe the illusion works because the gradient of the central hole makes it appear as if the viewer is entering a bright hole, causing participants’ pupils to constrict.
according to dr Dale Purves, a neurobiologist and professor emeritus who studies visual perception at Duke University, the study addresses a fundamental problem faced by all animals, including humans.
Purves told the Times that while a camera can directly measure the amount of light it’s taking in, “we don’t have that physical apparatus, we don’t have a measure of the world.”
dr Laeng said in the same article that when your eye is presented with a scene, your brain “analyzes what it’s seeing and builds, constructs a possible scenario, and adapts to it.”
That’s because a stimulus like light takes time to reach sense organs, which have to send it to the brain, which in turn has to process that information, make sense of it, and do something with it.
And by the time our brain catches up with the present, time has already passed and the world has changed.
To get around this, the brain may be constantly trying to predict a little bit into the future to anticipate the present in a survival instinct.
https://www.the-sun.com/lifestyle/5541114/mind-boggling-optical-illusion-bright-dark-eye/ Stunning optical illusion tricks brain into seeing white glow – and shows how your eyes are lying to you