Victor Sharrah had always had keen vision. But after a life-changing event in November 2020, he suddenly realized that the faces of the people around him looked demonic.
Their ears, noses, and mouths were stretched back, and there were deep furrows on their foreheads, cheeks, and chins.
“My first thought was that I had woken up in a world full of demons,” said Sharrah, 59, of Clarksville, Tennessee. “You can't imagine how scary it was.”
Someone he knew who taught visually impaired people suggested that he might have Prosopometamorphopsia, or PMO, in English. This extremely rare neurological disorder of perception causes faces to appear distorted in shape, size, texture or color. Sharrah felt the symptoms matched, and last year she was formally diagnosed with the condition.
Distortions only appear when individuals are seen in person, not in photographs or on computer screens.
This gave scientists the opportunity to visualize what the deformed faces of a person with PMO look like, something that had never been possible before. Dartmouth College researchers They created a digital representation of what Sharrah has been experiencing. The resulting images were published this Thursday in The Lancet.
To create the images, the researchers asked Sharrah to describe the differences between photographs of people's faces and the images in front of her. Investigators then used a photo editing program to alter the images to match Sharrah's description.
PMO symptoms usually disappear within a few days or weeks, although in some cases they can persist for years. Sharrah claimed that he keeps seeing demon-like faces.
There are less than 100 case reports of PMO. Researchers suspect that the condition is caused by a dysfunction in the brain network responsible for facial processing, although they do not fully understand what triggers the condition. Some cases have been linked to head trauma, stroke, epilepsy or migraines, but other people suffer from PMO without obvious structural changes in the brain.
Investigators pointed to two possible triggers in Sharrah's case. First, she suffered carbon monoxide poisoning four months before her PMO symptoms began. Second, she suffered a major head injury at age 43: While she was trying to unclog the handle of Sharrah's trailer, she fell backwards and he hit his head on the cement. According to the study, MRIs showed a lesion on the left side of the brain.
Lead author of the study Antônio Mello, a doctoral student working in Dartmouth's Social Perception Laboratory, said other people have come to the lab with PMO symptoms that differ markedly from Sharrah's.
Some people “have seen facial distortions for as long as they can remember, since they were children,” Mello stated. “At least for them, it is impossible to find a single event (in their lives) that could be responsible.”
Researchers even suspect that the condition may be underrecognized by doctors.
“Every week or two we hear from someone new” who describes symptoms consistent with PMO, said Brad Duchaine, one of the study's authors and principal investigator at the Social Perception Laboratory.
He added that some patients he has worked with in the laboratory “don't tell anyone or tell very few people, because they are afraid of what others will think.”
Additionally, Mello expanded, many doctors are not aware of PMO and may misdiagnose people with mental health disorders instead. As a result, some PMO patients have been prescribed medications for schizophrenia or psychosiswhich are not appropriate for his condition, he explained.
A key difference between PMO and psychological disorders, Mello said, is that people with PMO “don't think that the world is really distorted, they just realize that there is something different with their vision.”
Although there is some overlap in the symptoms that various PMO patients describe, there is also quite a bit of variation, Duchaine said. So the images from Sharrah's case may be unique to her experience.
Duchaine said she has talked to people who see droopy faces, as well as a woman who sees two faces when she looks at someone, one in front of the other. Another woman she spoke to recently sees “witch-like” faces, with long noses and pointed ears, she claimed.
“The first time it happened to him he was on a beach in Jamaica and he was looking at two women who were standing in the water. They had this witchy look one moment, and then they didn't,” she recounted.
A case study published in 2018 described a 68-year-old woman who developed PMO after a stroke. Although her neurological and eye exams were normal, she reported that people's left eyes moved up and to the side when she saw them in person or watched them on television. However, her own face looked normal to him in a mirror.
“On TV, I saw people with half their faces distorted, and it was the left half. Her stroke also occurred on the left side,” explained Nada El Husseini, one of the authors of the study and associate professor of Neurology at Duke University School of Medicine.
Husseini added that PMO symptoms may worsen when people look at moving faces, which could explain why some people don't notice facial distortion in photographs.
Sharrah stressed that this is consistent with her experience.
“When I look at a person, that face is moving, it is talking, it is gesturing. So it increases the effect,” she noted.
Said has found some ways to cope with his illness. He lives with a roommate and her two children, which, he says, has helped him because he is used to being around people, so he doesn't get as scared when he sees new faces in public. For reasons that researchers are not very clear about, Sharrah also believes that green light alleviates his symptoms, so he sometimes wears glasses with lenses of that color when he is around people.
He wants others to know that they can control the disease too.
“I was very close to being hospitalized,” Sharrah confessed. “My number one goal is to help someone overcome the trauma that I suffered and prevent them from being hospitalized and medicated for that reason.”