Sunday, May 5, 2019

Foreign accent syndrome 3


“Foreign Accent Syndrome” (FAS) is a rare disorder in which patients start to speak with a foreign or regional tone. This striking condition is often associated with brain damage, such as stroke. Presumably, the lesion affects the neural pathways by which the brain controls the tongue and vocal cords, thus producing a strange sounding speech.

Yet there may be more to FAS than meets the eye (or ear). According to a new paper in the Journal of Neurology, Neurosurgery and Psychiatry, many or even most cases of FAS are ‘functional’, meaning that the cause of the symptoms lies in psychological processes rather than a brain lesion.

To reach this conclusion, authors Laura McWhirter and colleagues recruited 49 self-described FAS suffers from two online communities to participate in a study. All were English-speaking. The most common reported foreign accents were Italian (12 cases), Eastern European (11), French (8) and German (7), but more obscure accents were also reported including Dutch, Nigerian, and
Croatian.  Participants submitted a recording of their voice for assessment by speech experts, as well as answering questions about their symptoms, other health conditions, and personal situation. 

McWhirter et al. classified 35 of the 49 patients (71%) as having ‘probably functional’ FAS, while only 10/49 (20%) were said to probably have a neurological basis, with the rest unclear.
These classifications are somewhat subjective in that there are no hard-and-fast criteria for functional FAS. None of the ‘functional’ cases reported hard evidence of neurological damage from a brain scan, but only 50% of the ‘neurological’ cases did report such evidence. The presence of other ‘functional’ symptoms such as irritable bowel syndrome (IBS) was higher in the ‘functional’ group.

In terms of the characteristics of the foreign accents, patients with a presumed functional origin often presented with speech patterns that showed inconsistency or variability. For instance, pronouncing ‘cookie jar’ as ‘tutty dar’ but being able to correctly produce ‘j’, /k/, /g/ and ‘sh’ sounds as part of other words.

But if FAS is often a psychological disorder, what is the psychology behind it? McWhirtner et al. don’t get into this, but it is interesting to note that FAS is often a media-friendly condition. In recent years there have been many news stories dedicated to individual FAS cases. To take just three:

American beauty queen with Foreign Accent Syndrome sounds IRISH, AUSTRALIAN and BRITISH

Scouse mum regains speech after stroke – but is shocked when her accent turns Russian

Traumatic car accident victim has Irish accent after suffering severe brain injury

Perhaps the popularity of FAS has become a self-fulfilling prophecy? I wouldn’t be surprised if people who have heard of FAS through the media are more likely to develop the syndrome themselves, in response to a stressful trigger event. 

http://blogs.discovermagazine.com/neuroskeptic/2019/03/09/curious-foreign-accent-syndrome/#.XM_VAuhKjIU


McWhirter L, Miller N, Campbell C, Hoeritzauer I, Lawton A, Carson A, Stone J. Understanding foreign accent syndrome. J Neurol Neurosurg Psychiatry. 2019 Mar 2. pii: jnnp-2018-319842. doi: 10.1136/jnnp-2018-319842. [Epub ahead of print]

Abstract

OBJECTIVE:
Foreign accent syndrome (FAS) is widely understood as an unusual consequence of structural neurological damage, but may sometimes represent a functional neurological disorder. This observational study aimed to assess the prevalence and utility of positive features of functional FAS in a large group of individuals reporting FAS.

METHODS:
Participants self-reporting FAS recruited from informal unmoderated online support forums and via professional networks completed an online survey. Speech samples were analysed in a subgroup.

RESULTS:
Forty-nine respondents (24 UK, 23 North America, 2 Australia) reported FAS of mean duration 3 years (range 2 months to 18 years). Common triggers were: migraine/severe headache (15), stroke (12), surgery or injury to mouth or face (6) and seizure (5, including 3 non-epileptic). High levels of comorbidity included migraine (33), irritable bowel syndrome (17), functional neurological disorder (12) and chronic pain (12). Five reported structural lesions on imaging. Author consensus on aetiology divided into, 'probably functional (n=35.71%), 'possibly structural' (n=4.8%) and 'probably structural' (n=10.20%), but positive features of functional FAS were present in all groups. Blinded analysis of speech recordings supplied by 13 respondents correctly categorised 11 (85%) on the basis of probable aetiology (functional vs structural) in agreement with case history assignment.

CONCLUSIONS:
This largest case series to date details the experience of individuals with self-reported FAS. Although conclusions are limited by the recruitment methods, high levels of functional disorder comorbidity, symptom variability and additional linguistic and behavioural features suggest that chronic FAS may in some cases represent a functional neurological disorder, even when a structural lesion is present.

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