This test helps people determine whether they should be driving at night or in the rain.
People are battling to see the numbers that are hidden in a swirling image, and it may say something about their driving.
The picture, posted to Twitter - now X - by @benonwine, shows a black and white striped circle with numbers concealed inside of it.
However, the image is tricky on the eyes as the line space and direction changes, making it hard to figure out what the numbers are.
“Do you see a number? If so, what number,” the caption reads.
Social media users flooded to the comments to reveal the numbers they saw in the optical illusion.
“45,283 … and what’s the catch? Should I book an appointment with my GP,” one person guessed.
Another said they could only make out a few numbers, but admitting to having an intense glasses prescription to help them spot the numbers.
Another wrote: “I can see 45,283, since looking at the other replies ... others are seeing two other numbers. I can see there are numbers there but can’t make them out.”
“3,452,839, but to be honest the first 3 is a bit of a guess. Can’t get a fix on it. Easier to see if you jiggle the image up and down, but I don’t know why,” another revealed.
One user said: “Initially 15,283 then I expanded the image and it became 3,452,839!”
The whole number in the optical illusion, which works by making use of contrast sensitivity, is 3,452,839.
Contrast sensitivity is the ability to perceive clear outlines of little objects, or being able to point out tiny differences in shadings and patterns.
A lack of contrast sensitivity could be an issue in real-life scenarios.
For example, actions that show a lack of contrast sensitivity include being unable to read when the paper and text are of a similar colour. Tripping over kerbs or steps and driving in certain conditions can also indicate a lack of contrast sensitivity.
People with reduced visual contrast sensitivity are urged not to drive in conditions with low light, fog, glare or rain.
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