A man from Yorkshire claims to have started speaking in a broad Irish accent after waking up from a brain operation. Why?
He's never even visited Ireland, but when Chris Gregory came round from brain surgery he reportedly started speaking like a native.
Mr Gregory had spent three days on a life-support machine after surgery. When he came round he sang a stirring rendition of Danny Boy from his hospital bed, much to the surprise of staff and his family.
His strange behaviour is thought to be the result of a very rare condition called Foreign Accent Syndrome (FAS). People who have it start speaking in an entirely different accent. In some cases they speak fluently in a language they hardly know.
Doctors believe it is triggered following a stroke or head injury, when tiny areas of the brain linked with language, pitch and speech patterns are damaged.
The result is often a drawing out or clipping of the vowels that mimic the accent of a particular country, even though the sufferer may have had limited exposure to that accent.
"This syndrome results in a very particular constellation of changes to the way a person speaks," says Professor Sophie Scott, from the Institute of Cognitive Neuroscience at University College London.
"They do not actually develop a whole new accent, it is the listener who attaches a particular label to what they are hearing. In the UK people are most likely to say someone with Foreign Accent Syndrome sounds French or German, while in the US people are mostly likely to be told they sound British."
There has been an estimated 50 recorded cases since the syndrome was first indentified in the 1940s. A slight increase in cases has occurred in recent years, but this is probably because researchers are now looking out for them, says Prof Scott.
One of the first reported cases was in 1941 when a young Norwegian woman developed a German accent after being hit by bomb shrapnel during a World War II air raid. She was shunned by friends and neighbours who thought she was a German spy.
"It can be a very distressing experience for people," says Prof Scott. "We tend to take our voices for granted but people don't like it when they don't sound like themselves. Society can be very judgemental when it comes to accents."
In 2006 Linda Walker, 60, woke from a stroke to find that her Geordie accent had been transformed into a Jamaican one. At the time she said she was devastated.
"I've lost my identity, because I never talked like this before," she said. "I'm a very different person and it's strange and I don't like it."
The condition can be permanent or last for a few hours. Some people get help to try learn how to speak in their usual accent again, but it can be a difficult process.
"Foreign Accent Syndrome changes the melody of your speech, the rhythms and specific sounds," says Prof Scott. "Changing that back to what it once was is not easy."