By Mary Carpenter
ONE DAY DC-resident P.W. began hearing music when none was playing —tunes that sounded a lot like the classical pieces recently featured on her public radio station. Pareidolia—also “Musical Ear Syndrome (MES)— is very common, although it can also be a sign of hearing loss or tinnitus or of mental health conditions such as schizophrenia.
The phenomenon of pareidolia—from the Greek words “para,” meaning in this case abnormal, and eidolon, spirit-image—results from the human tendency to seek patterns in randomness, writes Philip Jaekl on Nautilus. Most likely to induce audio pareidolia are sounds from motors—air-conditioners, especially old ones; jet planes; traffic—and running water.
The more common form of pareidolia is visual, from finding animals in clouds to seeing faces—along with perceiving their emotions and personality traits, such as on the fronts of cars. Not unlike her subjects in Vienna, Austrian researcher Sonja Windhanger found those in Ethiopia described cars with a big windscreen, round headlights and a small grill as “young and feminine,” while cars with “flatter headlights and a bigger, squarer under-body appeared older and more masculine.”
Rorschach inkblot tests make use of this tendency of the brain to seek visual patterns, with the idea that an individual’s choice—for example, seeing a bunny or a vulture—represents their unconscious thoughts or feelings. Also, in a test for “implicit bias,” known as the “weapons or tools task,” participants view photos of faces, white and Black, with each one followed by an image that could be either a weapon or tool: after being shown a Black face, many people are more likely to label the subsequent image a weapon than they did when the previous photo was a white person.
With Rorschach audio, hidden messages emerge from random sounds. Major retail chains removed “Little Mommy Real Baby Cuddle ‘n Coo” dolls after a parent heard in the doll’s babbling sounds, “Islam is the light”—in 2008, an election year when media messaging frequently connected Islam and terrorism. And “electronic voice phenomena” refers to the effort to record voices of ghosts that have been heard in random electronic noises.
“Sine wave speech”—composed of sound waves with none of the frequency patterns thought to signal natural speech—used in studies at Yale University found most listeners, when told ahead of time specific words that would appear in the track, heard those words. On the other hand, several participants not told any words ahead of time still managed to pick out a sentence, suggesting that brains work quite hard to find patterns when none exist.
One explanation is “sensory activity spill-over”—from those parts of the auditory system that might recognize that the sound is coming from a motor into different areas of the nervous system responsible for processing speech and language, according to the study’s lead author, psychologist Robert Remez, now at Columbia University.
But another explanation is “top-down,” because pattern recognition involves not just finding a pattern but also assigning meaning—using prior knowledge, context and expectations from other parts of the brain to aid perception. With no actual verbal content in the sounds of an air conditioner, according to London neuroscientist Chris Frith, “our top-down unconscious expectations may be given free rein to color the sensory input.”
While pareidolias appear to be limited to vision and hearing, the sense of smell may play a role in both—at least for infants, as their “perceptual development integrates information across the senses for efficient for efficient category acquisition,” according to French researchers. In their study, infant brains found face patterns in random images more quickly in the presence of maternal odors.
Feelings of eeriness and sometimes revulsion can accompany pareidolia, notably with virtual reality and other robotic recreations as well as with lifelike dolls. “Uncanny valley” refers to the increasing strength of such feelings that can occur, paradoxically, as humanoid objects come closer to looking and sounding like real humans. But similar eerie sensations that can accompany finding meaningful connections or patterns where none exists can also be an early sign of schizophrenia.
“Anomalous auditory perceptions” is the focus of a discussion forum created by audiologist Neil Bauman at his Center for Hearing Loss in southern Pennsylvania—where participants often worry that hearing such sounds could indicate mental illness. Hallucinations refer to any sensory perception of something not really present, but perceiving voices with the knowledge that they are not real is very different from believing the voices are present —and becoming fearful or even taking steps to get out of harm’s way. Remez explains the difference between resemblance and identification—between thinking X is like Y, and believing X is Y. But, he told Jaekl, “I wish we knew more about that distinction.”
Just the experience of learning more about pareidolias and how common they are often reduces the frequency or intensity of these experiences. Although P.W.’s doctors ruled out any form of illness in her ears or elsewhere, when she found out that better understanding pareidolia might make her music fade or disappear altogether, she didn’t want to hear any more. Instead she started listening to recordings of Willie Nelson—with the hope that he might join what she calls her “mystery musicians.”
—Mary Carpenter regularly reports on topical subjects in health and medicine.