Health

Dr Rod Pearce

One syndrome which tests our neurological diagnostic skills is the so-called foreign accent syndrome (FAS).

It is a rare motor speech disorder which causes patients to speak their native language with an accent.

This non-native way of speaking is the result of changes in their speech which, according to a 1982 definition, are the consequence of damage to the central nervous system.

Often, the cause is a stroke or brain trauma affecting the languagedominant areas of the brain, usually the left side just behind the frontal lobe.

But FAS has also been associated with other causes and been described in association with multiple sclerosis and cancers (primary or secondary). Sometimes, despite the best X-ray or MRI, no cause is evident.

There are reported cases of patients speaking differently after trauma (such as a car crash) but no abnormality is seen on brain X-rays.

The more common form of FAS is where an abnormality is found in the brain. This discovery came about in the past by looking at the brain post-mortem but now by use of new imaging techniques.

Disputed still is the possibility that, following a head injury, concussion might cause the accent to change.

Broadly, FAS probably falls under the diagnosis of a form of aphasia.

Aphasia is usually a symptom of brain injury. It can present in many forms because the way we are able to speak requires multiple parts of the brain. It is a complicated process.

Aphasia might present through: • Speaking in short or incomplete sentences. • Speaking in sentences that don't make sense. • Substituting one word for another or one sound for another. • Speaking unrecognizable words. • Difficulty finding words. • Not understanding other people’s conversation. • Not understanding what one reads. • Writing sentences that don't make sense.

Because speech is such a complex neurological process it is not unreasonable to think that, by chance, someone might, after a brain injury, seem to be speaking his or her native tongue with an accent.

The most common cause of aphasia is brain damage resulting from a stroke — the blockage or rupture of a blood vessel in the brain.

Loss of blood to the brain leads to brain cell death or damage in areas that control language. The ability to recover depends on the severity of the original injury or damage to the brain.

Stories of FAS date back to the 1900s. Although brain damage can usually be found in these cases, there are a dozen or so in those 100 years where no damage is found.

A neurologist described one of the most famous cases in which brain damage was clear.

During a German air raid over Oslo in 1941, shrapnel struck a 30-year-old Norwegian woman on the left side of her head. She suffered Broca’s aphasia – a defect in which part of the brain which co-ordinates speech is damaged and causes an inability to produce language – and a seizure disorder. Because speech is such a complex neurological process it is not unreasonable to think that, by chance, someone might, after a brain injury, seem to be speaking his or her native tongue with an accent.

Within a year, her language improved but her speech had an altered rhythm and melody suggesting a foreign accent, and she had never left her country.

The respected neurologist Georg Herman Monrad-Krohn described this incident in a detailed 1947 case report. The study led to the term foreign accent syndrome.

Since this famous case, around 40 individuals with FAS have been described in world literature.

Reported accent changes include Japanese to Korean, British English to French, US English to British English, and even Spanish to Hungarian.

The changes in speech – variations in melody, intonation, pauses, stresses, intensity, vocal quality and accents – might be more about our interpretation rather than a real disorder. Perhaps making us think it must be a different language accent rather than just a change in the way someone is talking.