Humans Face Pareidolic Experiences to Our Advantage

We are wired to find faces everywhere, and this instinct reveals how our perception and our environment can influence each other.

Tree with a face, Heald Green by Benjamin Shaw, CC BY-SA 2.0, via Wikimedia Commons

By Irina Matuzava

Imagine that you notice an unfamiliar male face out of the corner of your eye. You turn to look at it, but it turns out that you perceived a face-like visual cue—a tree adorned with several hollows that appear like “eyeholes.”

This kind of accidental perception of a meaningful image, such as a human face, in an otherwise random or unintended pattern—shapely clouds, pitted rock surfaces, or recessed wall sockets—is known as pareidolia. The phenomenon is not a disorder, but a normal feature of human vision and brain function. Some disorders do exacerbate the occurrence of pareidolic experiences, but in both normal and disordered visual perceptions, pareidolia offers a window into our brain’s operation when it needs to make quick, survival-oriented decisions.

It not only shapes our perception but also influences how we design objects, architecture, and navigate our environments. Facial pareidolia falls under the broader category of apophenia, the tendency to perceive patterns or connections in unrelated visual cues, noises, or concepts.

First described in relation to psychosis, apophenia is now recognized to occur in healthy people as well. The Rorschach test, for instance, used by psychologists as a metric for thought disorders, relies on the phenomenon that our brain searches for “known patterns” in otherwise ambiguous information. Apophenia takes many forms, with facial pareidolia being the most well-known and studied. Other types of pareidolia often involve auditory cues, music, objects, and architecture.

Auditory pareidolia occurs when people perceive or “hear” meaningful sounds in “seemingly static background noise,” according to Live Science. This includes hearing your name in a cacophonous venue when no one is calling or perceiving somewhat intelligible voices in the ambient hum of a refrigerator. Musical pareidolia, sometimes referred to as Musical Ear Syndrome, is a similar phenomenon. One might perceive music or singing in noises that are not musical. For instance, the noise being made by a fan might sound like musical notes or a string of notes to some people.

Object pareidolia and pareidolia in the built environment are sometimes different from one another based on the source of a given visual cue, but both often involve the perception of nonexistent faces. Everyday household objects, such as appliances and plugs, can appear as faces. Car “faces” can also be perceived to convey emotion, especially as some headlights are slanted and “angry,” or rounded and “friendly,” and so on.

Pareidolia in the built environment has been studied by researchers Chen Wang, Liangchen Yu, Yiyi Mo, and others, who published their research in the International Journal of Environmental Research and Public Health in 2022. This study stems from the idea that building facades can suggest expressive “faces” based on the style and placement of windows, doors, balconies, ledges, and other architectural elements. “The facial expressions perceived in house design through pareidolia can evoke the emotion of the observers,” the study stated.

With facial pareidolia, firing “alarm bells” when sensing that danger might be nearby is much less costly than missing a potentially dangerous predator or person. From an adaptive standpoint, sensing danger and being alert when encountering an unfamiliar face can save an individual’s life, especially before that individual can determine whether the face belongs to a friend or is someone/something posing a threat.

Crucially, the perception of illusory faces is strongest in our peripheral vision, where detail is limited. There are two types of photoreceptors in our eyes, rods and cones, which “are specialized for different aspects of vision.” Rods are highly sensitive to light, are responsible for vision at low light levels (scotopic and achromatic vision), and have low spatial resolution. Cones support color (photopic) vision, but they are less sensitive to light than rods. At the edges of vision and at low levels of light, rods dominate, so cone input is minimal¹. Thus, pareidolia reflects a low-detail and rapid response rather than a reflective interpretation of visual cues, especially in low light and at the periphery.

The 2022 study showed that pareidolian images in the built environment are more quickly and easily detected in the early morning and at midnight than during well-illuminated times, such as midday². The research questionnaire used by this study showed that a person’s susceptibility to pareidolic illusions depends on numerous factors, such as age, gender, lifestyle (including smoking, drinking alcohol, and insufficient sleep), medication use, and medical disorders, which influence one’s propensity for perceiving nonexistent patterns.

Respondents who were more than 40 years of age were much more likely to experience facial pareidolia, and women have been found to be more sensitive to pareidolia in the built environment throughout several studies. Women are more likely to report seeing faces in plates of food, for example³. In addition, people are more likely to identify pareidolian faces when exhausted.

Previous studies have shown that pareidolia is frequently observed in patients with Lewy body dementia, as well as those with Parkinson’s disease (PD). A study by Kentaro Kurumada and others (2021) showed that having PD increases the risk of visual hallucinations and experiencing pareidolia, more than another common neurodegenerative disorder or having multiple system atrophy⁴. A study of healthy subjects and patients with left- and right-hemispheric strokes (Camenzind et al., 2024) reported that pareidolia production decreases after a stroke. Patients experienced fewer of these experiences regardless of which side their lesion was on, but patients with a lesion in the right hemisphere produced the lowest pareidolic output. Notably, only “body parts” pareidolia, “where subjects perceived a pareidolia such as… a hand, a leg, or other parts of the body,” reduced after lesions in the left hemisphere, stated a 2024 study published in the journal Heliyon. This supports the hypothesis that the right hemisphere of the brain is more involved in global stimuli processing than the left, which is more engaged with local processing⁵.

Face recognition, in general, has traditionally played an important role in cognitive science, especially regarding research about object permanence and affective computing⁶. Cognitive scientist Susan G. Wardle became interested in pareidolian faces as a child and, in 2022, published a study with researchers Sanika Paranjape, Jessica Taubert, and Chris I. Baker investigating whether “illusory faces in inanimate objects are readily perceived to have a specific emotional expression, age, and gender.”

Human faces contain a plethora of social information: we can evaluate how old we think a person is, their gender expression, the emotion they convey, and other traits linked to or ascribed to facial features, such as trustworthiness⁷. Wardle and her fellow researchers conducted a series of large-scale experiments focusing on behavioral responses to perceived faces and found that illusory faces are able to convey the same kind of information as real faces. Though the faces were perceived in inanimate objects such as teapots, fruit, and electrical sockets, participants indicated whether they thought the objects were male, whether they were younger or older, and what emotion the object was supposedly expressing⁸.

Interestingly, pareidolic faces are more often discerned as male rather than female, especially when there is little visual information to accompany the “face.” In a Scientific American podcast episode titled “Does This Look Like a Face to You?”, Wardle briefly discussed her study and a few real-world applications of her results: a smiley face or emoji is generally perceived as male without additional accessories or features, like eyelashes and hairstyles. The same is true of other toys or characters, such as Lego characters.

Illusions can be playful, and at other times, informative or diagnostic, as with the Rorschach test. Because humans are sensitive to faces and face-like patterns, designers and architects should consider this tendency when designing commonly viewed, everyday objects or making changes to architectural features to produce more welcoming spaces. In the built environment, face-like house facades trigger responses in people’s stress levels, with respondents to a picture-based questionnaire describing certain houses as “scary” or “creepy.” Respondents generally disliked any face-like building facades, whether intentionally built in that manner or part of an illusory experience.

Regarding angles and overly geometric designs, the bouba-kiki effect shows that softness in angles is also associated with soft speech and sounds⁹. Rounded, soft shapes are generally paired with softer-sounding words, like “bouba,” and sharper, angular shapes are paired with harsher sounds, like “kiki.” On the other hand, objects that elicit face pareidolia are often prioritized by our visual system, something an artist can consider when enhancing or drawing attention to a particular feature in their work.

It is possible that artists from 40,000–10,000 BCE considered pareidolia as they created figurative art. Art found in the caves Las Monedas and La Pasiega, located in Cantabria, Spain, suggests that Upper Paleolithic artists integrated the natural features of cave walls into their figures. Both La Pasiega and Las Monedas are rich in animal figures as well as abstract signs and engravings. The animal figure paintings at Las Monedas depict horses, goats, bison, and reindeer. In the paper “Conversations with Caves,” researchers Izzy Wisher, Paul Pettitt, and Robert Kentridge point out that pareidolia facilitated the production and placement of the art by providing cognitive “cues” for the shapes carved or drawn¹⁰.

Previously misunderstood in clinical psychology, pareidolia is deeply human and may have given us an evolutionary advantage. Seeing faces can be scary, but the phenomenon keeps us alert when we come face-to-face with our foes. As the literature and research efforts on apophenia and subtypes of pareidolia grow, so does our understanding of ourselves, how we choose to adorn our environments, and how both natural and built environments affect our well-being.

¹ Purves, D; Augustine, G.J.; Fitzpatrick, D, et al. (eds.). “Functional Specialization of the Rod and Cone Systems.” In Neuroscience. Second edition. Sunderland (MA): Sinauer Associates. (2001).

² Wang, C.; Yu, L.; Mo, Y.; Wood, L.C.; and Goon, C. (2022). “Pareidolia in a Built Environment as a Complex Phenomenological Ambiguous Stimuli.” International Journal of Environmental Research and Public Health. Vol. 19, Issue. 9.

³  Pavlova, M.A.; Scheffler K.; and Sokolov A.N. (2015). “Face-n-Food: Gender Differences in Tuning to Faces.” PLOS One.

⁴ Kurumada, K.; Sugiyama, A.; Hirano, S.; Yamamoto, T., Yamanaka, et al. (2021). “Pareidolia in Parkinson’s Disease and Multiple System Atrophy.” Parkinson’s Disease.

⁵ Camenzind, M.; Göbel, N.; Eberhard-Moscicka, A.K.; Knobel, S.E.J., et al. (2024). “The Phenomenology of Pareidolia in Healthy Subjects and Patients With Left- or Right-Hemispheric Stroke.” Heliyon. Vol. 10, Issue. 5.

⁶ Chalup, S.; Hong, K.; and Ostwald, M.J. (2010). Simulating Pareidolia of Faces for Architectural Image Analysis.” Open Research Newcastle.

⁷ Willis, J. and Todorov, A. (2006). First Impressions: Making up Your Mind After a 100-ms Exposure to a Face. Psychology Science.

⁸ Wardle, S.G.; Paranjape, S.; Taubert, J.; and Baker, C.I. (2022). “Illusory Faces Are More Likely to Be Perceived as Male Than Female.” Proceedings of the National Academy of Sciences of the United States of America. Vol. 119, Issue. 5, pp. 1–12.

⁹ Peiffer-Smadja, N. and Cohen, L. (2019). “The Cerebral Bases of the Bouba-Kiki Effect.” NeuroImage. Issue 186, pp. 679–689.

¹⁰ Wisher, I.; Pettitt, P.; and Kentridge, R. (2024). “Conversations with Caves: The Role of Pareidolia in the Upper Paleolithic Figurative Art of Las Monedas and La Pasiega (Cantabria, Spain).” Cambridge Archaeological Journal. Vol 34, Issue. 2, pp. 315–338.

Irina Matuzava is a writer and researcher. She is a contributor to the Human Bridges project.

This article was produced by Human Bridges.