MIT-led study attempts to shed light on classic visual illusion

Researchers at the Massachusetts Institute of Technology (MIT) conducted a study that looks into what is considered a classic visual illusion.

If an individual were to look at two gray dots on a background with a gradient from light gray to black, no one could blame them if they thought the dots looked similar when, in reality, they appear very different based on their location on the background, MIT News. 

Scientists have studied the illusion, which is known as simultaneous brightness contrast, for more than a century, according to MIT News.

This year, the Boston-based institution is at the forefront of the study that deduces the role brightness estimation plays. Scientists even studied blind children in India and determined that they were susceptible to this illusion almost immediately after going surgery.

“All of our experiments point to the conclusion that this is a low-level phenomenon,” Pawan Sinha, a professor of vision and computational neuroscience in MIT’s Department of Brain and Cognitive Sciences and the study’s senior author, told MIT News. “The results help answer the question of what is the mechanism that underlies this very fundamental process of brightness estimation, which is a building block of many other kinds of visual analyses.”

A key takeaway from the study provided by Sinha is that people’s brains perceives a certain brightness at each location of the image but brightness precepts don't always align to the amount of light radiating from the image regions.

“The brain is presented with the challenge of figuring out how light or dark a surface is based on just the amount of energy it's receiving,” Sinha told MIT News.

The study is published in the August issue of Vision Research. Sinha co-authored the paper with Sarah Crucilla, Tapan Gandhi, Dylan Rose, Amy Singh, Suma Ganesh, Umang Mathur and Peter Bex.