In 1941, a Norwegian woman's brain was damaged by shrapnel during a German bombing run. As she recovered from the head injury, she began to speak her native Norwegian language in a heavy German accent. Her doctors were at a loss to explain this phenomenon, although some villagers began to suspect the woman of being a German spy or collaborator. She was eventually shunned by her fellow villagers, never regaining her natural Norwegian accent. Her extremely rare condition would enter the medical books as foreign accent syndrome.

Foreign accent syndrome is so rare that most sources report fewer than 20 cases worldwide since 1941. Virtually every case of foreign accent syndrome has appeared following a traumatic brain injury, aneurism or stroke. The patient may recover normally from the initial trauma, only to begin speaking with a foreign accent several weeks or months later. Some medical professionals initially suspected that foreign accent syndrome was a psychosomatic condition, but further research showed that almost all victims suffered damage in a specific section of the brain that controls language.

Those rare individuals with foreign accent syndrome are often troubled by its unexpected onset. Family, friends and the media may all become fascinated by the sudden accent change, putting a very public face on what should have been a private recovery time. Medical and language researchers may also want to put a patient with foreign accent syndrome through a battery of tests. Some patients have been known to recover their original accents, but many do not.

One theory concerning foreign accent syndrome is that the sufferer is not actually speaking in a foreign accent at all, but the listener assigns one based on inflections and emphasis. Several Americans diagnosed with foreign accent syndrome are said to speak in a British accent, even though they have never visited the United Kingdom and have been raised in areas with strong native accents, such as New York. Some researchers believe the patients are actually speaking a form of damaged English caused by the initial injury to the brain's language center. What listeners perceive as a clipped British accent may in actuality be a slurring of Americanized speech.

Foreign accent syndrome is not considered a life-threatening condition, but those who suffer from it may feel a great deal of social anxiety or suffer from agoraphobia, the fear of crowds and public spaces. Communication is a vital part of anyone's quality of life, so those diagnosed with foreign accent syndrome often feel a sense of frustration when they can no longer recognize their own voices.