"Um actually you have this super rare condition called prosopometamorphopsia! The people around you are definitely not demons!" "I HATE THE ANTICHRIST!!! I HATE THE ANTICHRIST!!!"

Victor Sharrah had always had sharp vision. But one life-altering day in November 2020, he noticed out of the blue that people's faces around him looked demonic.

Their ears, noses and mouths were stretched back, and there were deep grooves in their foreheads, cheeks and chins.

“My first thought was I woke up in a demon world,” said Sharrah, 59, of Clarksville, Tennessee. “You can't imagine how scary it was.”

Someone he knew taught visually impaired people and suggested he might have prosopometamorphopsia, or PMO. The extremely rare neurological disorder of perception causes faces to appear distorted in shape, size, texture or color. Sharrah felt the symptoms were a match, and he was formally diagnosed last year.

The distortions appear only when he sees people in person — not in photographs or through computer screens.

That gave scientists an opportunity to visualize what the warped faces look like for a person with PMO, something they had never been able to do before. Researchers at Dartmouth College created a digital representation of what Sharrah has been experiencing. The resulting images were published Thursday in The Lancet.

To create the visuals, the researchers asked Sharrah to describe the differences between photographs of people's faces and the real-life people standing in front of him. The researchers then used image-editing software to modify the pictures to match Sharrah's description.

PMO symptoms often resolve after a few days or weeks, though in some cases they can linger for years. Sharrah said he still sees demonic faces.

There are fewer than 100 published case reports of PMO. Researchers suspect it is caused by dysfunction in the brain network that handles facial processing, though they don't fully understand what triggers the condition. Some cases have been linked to head trauma, stroke, epilepsy or migraines, but other people have PMO without obvious structural changes in their brains.