Pareidolia: The Intriguing Reason We See Faces Everywhere

The world is full of faces – in wall outlets, lamp switches, and even cheese graters. Sometimes these faces hold religious meaning, like the women who found an image of the Virgin Mary in her grilled cheese sandwich (which she later sold for $28,000) or the Cheeto that strikingly resembles Jesus.

The widespread phenomenon of seeing faces in unexpected places – like clouds, buildings, and tacos – is so common that it has a name: pareidolia. Derived from Greek, pareidolia means 'beyond form or image,' and refers to perceiving patterns or meaning where none exist, such as hearing a heartbeat in white noise or thinking a seat cushion is angry at you.

It’s easy to brush off pareidolia as a harmless optical illusion or, worse, as a sign of a psychotic disorder. However, some researchers now argue that our remarkable tendency to perceive faces in ordinary objects reveals a deeper understanding of how our brains process the world around us. Rather than simply interpreting visual cues to identify an apple, a tree, or a face, it could be the reverse — what if our brains are actually instructing our eyes on what to see?

We Are Hardwired to Spot Faces

Kang Lee, a professor of applied psychology and human development at the University of Toronto, has spent years studying how we process faces. In addition to his popular TED Talk on how to detect if children are lying, Lee has focused on how infants, children, and adults recognize faces.

"From the moment we are born, we start searching for faces," Lee explains, emphasizing that this behavior is an outcome of millions of years of evolution. "One reason is that our ancestors had to identify predators or prey, all of which had faces. Another reason is that humans are highly social creatures. In our interactions, we need to distinguish between friend and foe."

Pareidolia might have an evolutionary explanation as well. The ability to instantly recognize faces could be crucial for survival. It's far more dangerous to miss seeing the lion's face lurking in the underbrush than to mistake an orange-and-black flower for it. The brain is more likely to generate a "false positive" (pareidolia) because it's better to be on alert for real threats.

Which Comes First, the Eyes or the Brain?

It's evident that evolution has wired our brains to prioritize faces, but what exactly happens beneath the surface? That's what Lee sought to uncover.

Traditionally, it’s believed that the eyes capture external visual stimuli like light, color, shapes, and motion, then send this data to the visual cortex in the occipital lobe of the brain. Once the occipital lobe processes this data into images, it’s sent to the frontal lobe for advanced interpretation. Is it just a rock formation, or could it be a giant head?

The traditional model that Lee refers to as "bottom-up" processing suggests that the brain merely passively receives information and tries to make sense of it. If we see faces everywhere, it's because the brain is reacting to stimuli that resemble faces — essentially any arrangement of spots and gaps that could resemble two eyes, a nose, and a mouth.

However, Kang and other researchers started to question this bottom-up approach. They wondered if the process might actually be the opposite — a "top-down" model where the brain takes control and leads the way.

"We wanted to explore if the frontal lobe plays a crucial role in helping us perceive faces," explains Lee. "Rather than face imagery coming from the outside, the brain might first form an expectation in the frontal lobe, which then sends it to the occipital lobe and ultimately to our eyes, allowing us to see faces."

'Seeing Jesus in Toast'

This line of questioning led Lee to consider pareidolia. Having read about people claiming to see figures of Jesus, Elvis, and angels in their toast and tortillas, he wondered if he could design an experiment to test the phenomenon.

Lee conducted an experiment where he hooked participants up to fMRI scanners and showed them blurry images, some containing hidden faces and others just static noise. The participants were told that half of the images had faces (which wasn’t true) and were asked, 'Do you see a face?' As a result, they reported seeing a face 34% of the time, even when the image was just noise.

What intrigued Lee most were the results from the real-time fMRI scans. When participants thought they saw a face, the 'face area' of their visual cortex activated, even though no face was present. This led Lee to believe that another part of the brain must be signaling the visual cortex to perceive faces.

In their paper titled, 'Seeing Jesus in toast: Neural and behavioral correlates of face pareidolia,' Lee and his team concluded that when the brain is 'primed' to see faces, the expectation to perceive a face originates in the frontal lobe, particularly the inferior frontal gyrus.

Lee describes the inferior frontal gyrus as a fascinating part of the brain, explaining, 'It’s responsible for generating ideas and guiding the visual cortex to interpret them. If the idea is a face, it sees a face. If the idea is Jesus, the cortex will certainly see Jesus. If the idea is Elvis, then Elvis will appear.'

Lee's 'Jesus in toast' paper earned him a 2014 Ig Nobel Prize, a playful accolade given by the humorous science magazine Annals of Improbable Research. Lee believes, however, that the pareidolia experiment revealed how top-down processing is crucial in shaping our perceptions of the world.

Lee says, 'A lot of what we perceive in the world doesn't come from our eyes, but rather from our minds projecting those perceptions onto what we see.'

Friend or Foe?

Lee has conducted research on babies and racial bias, discovering that newborns could recognize faces from all racial backgrounds but gradually lost this ability by nine months. By then, they could only differentiate between faces of their own race, due to the fact that, for the first nine months, they were primarily exposed to faces of the same race (usually their parents).

Through his studies, Lee has come to the conclusion that racial biases are not inherently biological; instead, we tend to trust individuals who resemble the faces we encountered during the early stages of our brain development. Unfortunately, this early preference can later evolve into various types of biases influenced by societal messages and stereotypes.

"The root of racial bias lies in our formative experiences," says Lee. "If we provided children with a more diverse visual and social environment, they would be less prone to developing such biases."

Fortunately, parents and educators have the power to counteract racial bias by introducing young children to faces of various races and addressing them by name, like "Jill" or "Derek," rather than categorizing them as a "white person" or a "Black person."