Headache-Inducing Spiral Illusion Explained
From
https://www.livescience.com/23094-spiral-circle-illusion-explained.html
Headahttps://www.livescience.com/23094-spiral-circle-illusion-explained.htmlche-Inducing Spiral Illusion Explained
By Natalie Wolchover | September 11, 2012 03:25pm ET
Warning: This optical illusion might give you a headache. At a glance, the swirls of tilted black-and-white squares create the perception of a spiral. Look more closely and you realize that the squares don't form a coil at all; they trace out four perfectly round, concentric circles. The cognitive dissonance between your overall impression of spiraling and your recognition of individual circles
well, it hurts.
The illusion called the "intertwining illusion" has been a hit on social media recently, and it also happens to be the subject of study by researchers around the world. Because optical illusions harness the shift between what the eyes see and what the brain perceives, teasing out how that shift happens enables scientists to understand the inner workings of the human visual system.
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