Do you see Jesus in your morning toast or the Virgin Mary on a potato chip? Turns out that's perfectly normal, according to a new study by Canadian and Chinese researchers. “Our findings suggest that it's common for people to see non-existent features because human brains are uniquely wired to recognize faces,” says lead researcher Kang Lee. Lee and his colleagues showed participants random pixelated images that were simply "noise," Lee says, but 35% of subjects spotted faces or letters when researchers told them such images were there. The researchers used MRI technology to monitor the brain activity of the subjects and determined that the frontal cortex, where expectations are generated, sent signals to the posterior visual cortex, which processes the images a person sees.
In other words, as Lee puts it, "believing is seeing," and we see what we expect to see. "What we have shown is that a lot of what we see and perceive is actually determined by biases that already exist in our brains" before our brains process an image we're seeing, he explains to CBC. That's why, while some people see Jesus on their sandwich, others might see Buddha. The phenomenon, known as face pareidolia, has been known for centuries. (Some of the images, most famously a toasted cheese sandwich on which the Virgin Mary was detected, have been sold for large sums of money, the Toronto Star notes). But until now, the brain process behind it was a mystery, and people who saw nonexistent images were sometimes thought to be "crazy," Lee says. Among the better known instances of this occurring: the "Virgin Mary tree", "Google Earth Jesus" and "Griddle Virgin."