(PORTLAND, Ore.) -- Karen Butler is from Oregon, not England. Yet, if you heard her speak, you'd think otherwise.
When asked where she got her accent, she says from her dental surgeon.
In 2009 Butler, a 56-year-old tax consultant in Toledo, Oregon, awoke from denture implant surgery with an accent that's a bit British with a Transylvanian twang, and it just sort of stuck.
"I had just had surgery, so at first we assumed it was because of all of the swelling," said Butler. "But within a week the swelling went down and the accent stayed."
Butler has foreign accent syndrome -- a condition so rare that only about 60 cases have been documented worldwide. Often preceded by a small stroke, the new drawl is thought to stem from a minor injury to a tiny area of the brain responsible for language pattern and tone.
"This is a very small part of the brain that controls the articulation and the intonation of speech that's affected, and that's why it's so rare," said Dr. Ted Lowenkopf, a neurologist and medical director of Providence Stroke Center in Portland, Oregon, in an interview with ABC News affiliate KATU-TV in Portland. "The chances to hit such a small area are more than a million to one in a stroke."
Because certain blood vessels in the brain are more prone to blockages, a stroke often damages parts of the brain responsible for language production and comprehension.
"Stroke happens in very predictable ways," said Dr. Julius Fridriksson, an associate professor of neuroscience at the University of South Carolina, who has seen many stroke patients but only a couple with foreign accent syndrome. "This type of damage is out of the ordinary."
Butler said she was never tested for a stroke because she felt fine.
"I appear to be completely normal otherwise," Butler said, adding that she never felt any pain or had neurological symptoms other than the change in her speech. "And I'm quite OK with [the accent]."
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