An optical illusion of a series of numbers hidden inside a swirling pattern of alternating black and white bands is going viral... because no one can agree on what numbers are actually hidden inside of the patterns.
The spirals are uneven which makes trying to figure out what numbers they see or if there are more numbers than they think.
Some people say they only see 528, and others say they see 45283.
But the correct answer is actually 3452839.
The illusion works by playing on contrast sensitivity, a measure of visual function, which allows us to perceive the difference between objects and their backgrounds.
Having better contrast sensitivity is helpful in low-light conditions and fog-like conditions to distinguish objects in spots where there is little contrast to begin with.