Beach or Car Door? Optical Illusion Confuses the Internet

A new optical illusion is doing the rounds on Twitter after one user posted an image of a car door that looks like a stormy beach.

"If you can see a beach, ocean sky, rocks and stars then you are an artist, But it's not a painting its lower part of the car gate which needs to be repaired," user @nxyxm wrote.

if you can see a beach, ocean sky, rocks and stars then you are an artist, But its not a painting its lower part of the car gate which needs to be repaired.

— X (@nxyxm) July 2, 2019

The photo has now been shared over 1,000 times with respondents unable to see the part of the car pictured. Helping people out, @nxyxm said: "Focus on dark side you will see car gate...It's a car door , the seal panel under it is damaged, the bend in the door gives illusion of beach , the seal panel is damaged and scratched which gives illusion of water on the edge of beach."

According to the National Institute of Heath's (NIH) Eye Institute, "an optical illusion is something that plays tricks on your vision." It relates to the way the brain and eyes work together to see an image—when looking at a 2D image, the brain can be tricked because it does not have all the information it needs to make sense of what is there, such as depth, lighting and position.

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Beach or car door? Muhammad Naeem

There are many famous optical illusions in existence and scientists use them to understand how the brain processes images. A study recently published in the journal JNeurosci looked at the Pinna-Brelstaff motion illusion. This is where thick lines arranged into circles appear to rotate when the person looking at them moves their head back and forth.

Brain scans showed that people process the illusion in the same way as they would a moving object, and that there was a processing gap of 15 milliseconds by neurons in the area of the brain that is critical for picking up visual motion. This is why the still image appeared to come to life.

Another famous illusion was recently used by scientists to predict the viewers' age. The image, in which people either see an old or young woman, was created by cartoonist W. E. Hill, 1915.

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The optical illusion by the cartoonist W. E. Hill. W E Hill

In a study published in Scientific Reports, researchers sought to find out if people's own age biases would affect subconscious face perception. And findings showed they did. Older people were more likely to see the old woman, while younger participants saw an image of a young woman.

Mike Nicholls, an author of the paper from Flinders, told Newsweek at the time: "We were interested in how individual differences in traits, such as age, cause people to see things differently. The most interesting thing is that this bias seems to be sub-conscious. The image was only shown for half a second and observers were not told that they would have to make a judgement of age."

optical illusion
An optical illusion where the image appears to be moving. iStock