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The illusion of light constricts pupils

Which of the figures below is brightest in the middle? Maybe when your brain plays tricks on you it isn’t a mistake, but rather a sort of improvement on reality.

Two round illustrations. The figure on the left is called “Morning sunlight”, and appears to have a bright light at the centre. The other one is called “Evening dusk”, and it seems to have a dimmer interior and a glowing corona.

These two illusions are made according to a design by the psychologist and artist Akiyoshi Kitaoka. The figure on the left is called “Morning sunlight”, and appears to have a bright light at the centre. The other one is called “Evening dusk”, and it seems to have a dimmer interior and a glowing corona. Both figures are actually equally bright, inside and outside. (Figures: Bruno Laeng, Tor Endestad and Akiyoshi Kitaoka).

It’s an old philosophical question: when you walk down the street, seeing, smelling, hearing and feeling the environment around you – to what degree are you experiencing reality as it is?

Animals’ and humans’ abilities to sense themselves and their environment have developed in the course of over a billion years of evolution. Still, sometimes it seems as if our brain is fooling us.

Illusions are a poignant example. In the picture above you see two forms put together from identical pieces. One of the forms seems to have a glowing centre. In the other the centre appears dimmer.

In reality the middle sectors of both are equally light. Our brain interprets it otherwise. It’s an optical illusion.

By freelance journalist Kristin Grønli
Published Feb. 9, 2012 11:35 AM - Last modified Feb. 9, 2024 1:39 PM