Expanding Hole Optical Illusion Will Boggle Your Mind, Tricks Pupillary Light Reflex

Photo credit: Suren Manvelyan
The Expanding Hole optical illusion has been causing a stir online today, and for good reason. Many – up to 86% of the people surveyed – will perceive the central black hole to be expanding, as if you’re moving into a dark environment, or falling into a hole. Put simply, it consists of a circular smear or shadow gradient of the central black hole evoking a marked impression of optic flow, as if you are heading forward into a hole or tunnel.

Researchers from the University of Oslo gathered 50 adult participants for this study and then proceeded to let them view 26 different versions of the Expanding Hole illusion, with each one in a different smear / dot color combination. The one you see above – a black smear with dots on a white background – generated the strongest reaction, with 43 participants reporting that the hole appeared to be expanding. Whatever the case may be, it’s all just an illusion, just like this infinity cube lamp.

DJI Mini SE – Camera Drone with 3-Axis Gimbal, 2.7K Camera, GPS, 30-min Flight Time, Reduced Weight, Less Than 0.55lbs / 249 gram Mini Drone, Improved Scale 5 Wind Resistance, Gray

• Light as a Smartphone – Weighing less than 0 55lbs / 249 grams, DJI Mini SE is roughly the same weight as the smartphone. In the United States and Canada, you can fly this camera drone without the need to register your drone with the local government.
• Capture on the Go – The lightweight and powerful DJI Mini SE camera drone is the ideal for creators on the move. The ultra-portable design allows you to effortlessly capture moments in unforgettable ways.
• More Time in the Sky – DJI Mini SE’s weight allows it to stay in the air longer than similar consumer drones on the market. Enjoy up to 30 minutes of flight time with a fully-charged battery.
• Capture the Detail – DJI Mini SE supports 12MP aerial photos and 2.7K HD videos. A 3-axis motorized gimbal provides superior camera stability and ensures clear ultra-smooth footage.
• Upgraded Wind Resistance – DJI Mini SE can resist 29-38kph winds and take off at a max altitude of 4,000 meters, so your footage is stable even when flying along a windy coastline or high above an alpine forest.

Here we show based on the new ‘expanding hole’ illusion that that the pupil reacts to how we perceive light – even if this ‘light’ is imaginary like in the illusion – and not just to the amount of light energy that actually enters the eye. The illusion of the expanding hole prompts a corresponding dilation of the pupil, as it would happen if darkness really increased,” said Dr Bruno Laeng, a professor at the Department of Psychology of the University of Oslo.