Imagine seeing faces look like demons? That's the reality faced by people who suffer from Prosopometamorphopsia (PMO), a rare condition often misdiagnosed as schizophrenia.

Prosopometamorphopsia is an extremely rare neurological disorder that alters visual perception, causing individuals to see distorted facial appearances, including shape, size, texture, or color. The condition has been reported in fewer than 100 cases.

Although the exact trigger remains unknown, experts believe it stems from dysfunction in the brain network responsible for facial processing. Some cases of PMO have been associated with head trauma, stroke, epilepsy, or migraines, while others experience the condition without evident structural changes in their brains.

In a study published in The Lancet, researchers created facial illustrations based on the description given by a patient, Victor Sharrah, who has been suffering from PMO for around 31 months.

The 58-year-old Sharrah experiences distorted facial appearances in every person he sees and describes them as "demonic." He perceives facial features as severely stretched with deep grooves on the forehead, cheeks, and chin. However, Sharrah does not see any vision changes when looking at objects such as houses or cars. The distortion happens only when he sees people in person, but not while seeing a picture or photograph and seeing it on a computer screen.

The researchers noted that the changes in his visual perception were not accompanied by delusional beliefs about the identities of the people he encountered.

To generate the visuals, the researchers asked Sharrah to describe the discrepancies between photographs of individuals' faces and the actual people standing in front of him. They then utilized image-editing software to adjust the pictures to align with Sharrah's descriptions.

Sharrah's case could potentially be triggered by two factors, according to researchers. Firstly, he experienced carbon monoxide poisoning four months before the symptoms began. Additionally, he suffered a significant head injury at age 43, and MRI scans revealed a lesion on the left side of his brain.

Many cases of PMO often get misdiagnosed with schizophrenia, according to Brad Duchaine, a co-author of the study. "We've heard from multiple people with PMO that they have been diagnosed by psychiatrists as having schizophrenia and put on anti-psychotics, when their condition is a problem with the visual system," Duchaine said in a news release.

"And it's not uncommon for people who have PMO to not tell others about their problem with face perception because they fear others will think the distortions are a sign of a psychiatric disorder. It's a problem that people often don't understand," Duchaine added.

Sharrah has, however, learned to cope with his condition. He uses green-tinted lenses when he goes in crowds as it reportedly alleviates his symptoms, although researchers could not explain the phenomenon.

"I came so close to having myself institutionalized. If I can help anybody from the trauma that I experienced with it and keep people from being institutionalized and put on drugs because of it, that's my No. 1 goal," Sharrah told NBC News.

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