Up until last week, if you claimed to see an image Jesus Christ on your toast or even in the clouds, you did so at the risk of ridicule — but not anymore, as U of T professor Dr. Kang Lee and his colleagues have identified the phenomenon as “face pareidolia,” which they describe as “the illusory perception of non-existent faces” in the abstract to their study Seeing Jesus in toast: Neural and behavioral correlates of face pareidolia.
“Our findings suggest that it’s common for people to see non-existent features because human brains are uniquely wired to recognize faces, so that even when there’s only a slight suggestion of facial features, the brain automatically interprets it as a face,” said Dr. Lee in the U of T media release.
The study was a collaboration between the Beijing Jiaotong University, Xidian University, the Institute of Automation Chinese Academy of Sciences, and the Dr. Eric Jackman Institute of Child Study at U of T.
20 Chinese subjects took part in the study and were shown five types of stimuli which incorporated images with either faces or letters of the alphabet. These hidden features were easy to detect in some of the cases and hard to detect in others. The fifth stimulus, used as the control measure, was pure-noise images, which contained neither faces nor letters. This allowed the researchers to compare the subjects’ behavioural and neural responses to images of faces to those to images of letters and potentially isolate the specific regions of the brain that were activated in the case of face pareidolia only.
The researchers ran 960 trials of the experiment and were able to identify that subjects who exhibited a considerable response in recognizing non-existent letters were also more likely to do the same for faces. In addition, the participants were told in advance that half of the images contained a face or letter within them, and half did not.
The results indicated that, in approximately 35 per cent of the cases, participants reported seeing a letter or face when none existed.
One of the more significant outcomes of the study was the understanding of the right fusiform face area — a part of the brain’s visual system that is specialized for the perception and recognition of faces. The researchers also found that it was only when face pareidolia took place, or when the subjects perceived a non-existent face, that the right fusiform face area showed heightened activation. They concluded that the right fusiform area is not only significant in the management of actual faces, but also in those of illusory ones.
The study affirms that the human predisposition towards detecting faces, as suggested by face pareidolia, is probably an adaptive mechanism, resulting from the social importance of faces in our lives.
