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Short report
Understanding foreign accent syndrome
  1. Laura McWhirter1,
  2. Nick Miller2,
  3. Catriona Campbell3,
  4. Ingrid Hoeritzauer1,
  5. Andrew Lawton4,
  6. Alan Carson5,
  7. Jon Stone
  1. 1 Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
  2. 2 Speech and Language Sciences, University of Newcastle, Newcastle upon Tyne, UK
  3. 3 Department of Clinical Psychological Science, Maastricht University, Maastricht, Netherlands
  4. 4 Department of Psychological Medicine, Royal Infirmary of Edinburgh, Edinburgh, UK
  5. 5 Department of Psychiatry, University of Edinburgh, Edinburgh, UK
  1. Correspondence to Dr Laura McWhirter, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH10 5HF, UK; laura.mcwhirter{at}ed.ac.uk

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.

  • conversion disorder
  • functional neurological disorder
  • stroke
  • migraine
  • speech
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Introduction

Foreign accent syndrome (FAS) represents a disorder of speech in which listeners perceive the affected individual as speaking with a foreign or different regional accent that is not their habitual accent. It has been reported as a result of stroke or other lesion within speech-motor networks, but there is increasing recognition of functional or psychogenic FAS.1–4 A 2015 systematic review identified 105 published case reports of FAS between 1907 and 2014 of which 15 met criteria for ‘psychogenic FAS’.2

Additionally, FAS could represent a functional neurological symptom even in patients with demonstrable structural lesions. Functional neurological disorder (FND) is a common reason for attendance at neurology outpatient clinics, with symptoms that are involuntary but internally inconsistent, and associated with distress and disability.5–7 Speech and language symptoms are not uncommon in patients with FND.8 There have been important changes over the last 20 years in approach to FND: now recognised to be not always stress related; and diagnosed on the basis of positive clinical signs rather than by exclusion, which crucially allows the diagnosis to be made in the presence of structural disease.9 10 Suggested positive features of functional FAS include accent inconsistency, ability to mimic other accents and periods of transient recovery of normal accent, indicating a different kind of disruption to speech-motor control.11

This study aimed to describe characteristics of a group of individuals with self-reported FAS, to estimate the proportion representing functional FAS and to evaluate the diagnostic value of specific speech and clinical features.

Methods

Participants were recruited from two unmoderated online FAS support groups, and survey details shared with colleagues internationally including via the Association of British Neurologists and Royal College of Speech and Language Therapists. Inclusion criteria were being over 18 and responding ‘yes’ to the question: ‘Do you believe that you may have a condition, sometimes called ‘foreign accent syndrome’, as a result of which you speak, for all or part of the time, with a voice or accent not your own?’

Participants completed a secure online survey including validated questionnaires assessing somatic symptoms (Patient Health Questionnaire 15 (PHQ-15)), depression and anxiety (Hospital Anxiety and Depression Scale (HADS)), social/occupational function (Work and Social Adjustment Scale (WSAS)) and illness perceptions (modified Illness Perceptions Questionnaire - Revised (IPQ-R)). Participants were invited to submit samples of speech, recorded via computer or smartphone, consisting of reading a standardised text (‘Rainbow Passage’) and spontaneous description of a standardised scene (‘Cookie Theft Picture’).

Clinical summaries were reviewed by authors JS, AC and LM who after discussion reached consensus about likely cause of the overall clinical picture in each case: ‘probably functional’, ‘possibly structural’ or ‘probably structural’. A ‘probably structural’ diagnosis was made where the respondent described a neurological event with investigation results in keeping with a neurological injury or illness corresponding with onset of the foreign accent. A ‘probably functional’ diagnosis was made where (1) no such neurological injury or illness occurred at onset and (2) other features were present which strongly suggested a functional disorder, such as marked inconsistency (but not spontaneous remission). Those where there were some features suggestive of a functional disorder but some uncertainty about a possible structural cause were classified as ‘possibly functional’.

The audio recordings supplied (including one video recording) underwent auditory-perceptual analysis by author NM and, independently, by another speech and language therapy professional, blind to clinical details. Spoken output was analysed in terms of severity and nature of speech changes with regard to respiration, voice, articulation, prosody, word finding and sentence structure. Perceived changes were examined for how far they conformed to standard diagnoses of dysarthria, apraxia of speech, dysprosody and aphasia, congruency between different levels of analysis and consistency internal to the different levels. On the basis of this analysis, the audio recordings were classified as ‘probably functional’, ‘possibly structural’ or ‘probably structural’.

Results

The survey, open 23.11.16–1.3.17, collected 49 responses: UK (24), North America (23) and Australia (2). Original accents were English—unspecified (25), English—American (20), Scottish (2), Australian (1) and Welsh (1).

Consensus classification was: 35 (71%) probably functional, 4 (8%) possibly structural (two stroke not visible on scan, one Parkinson’s disease one mild traumatic brain injury [TBI]) and 10 (20%) probably structural (eight stroke, one TBI and one severe headache with Bell’s palsy).

Clinical features

Onset was typically sudden and followed a significant event in all but one presentation. Forty-three had brain imaging (CT(33), MRI(38), Positron Emission Tomography (PET)(3)), four electroencephalography (EEG) and three lumbar puncture (table 1).

Table 1

Clinical features of patients with self-reported FAS

Many different accents were reported, with most participants reporting a number of different accents; some (22) indicated that their accent itself changed, and others (10) reported a consistent accent heard as different accents by different listeners. Reported accents included (1) foreign perceived accents (Italian (12), Eastern European (11), French (8), German (7), South African (6), Polish (5), Russian (4), Indian (3), Asian (3), Swedish (3), Chinese (3), French/Italian (2), Scandinavian (2), Czech/Slovak (2), European (2) and one each of Dutch, Nigerian, Japanese, Spanish, Belgian, Croatian, Norwegian and Balkans) and (2) a different accent of the native language (British (7), Irish (7), South African (6), Scottish (3), Welsh (2), Australian (2), Jamaican (1), Texas (1), North Dakota (1) and Canada (1)). In addition to one or more foreign accents, one respondent each reported ‘slurred and gibberish’ speech, ‘a child voice’, ‘bad stutter or ‘triple talk’ (sic), ‘a tendency to pick up stronger accents’ and one reported ‘I tend to say words backwards. And put the first letter of first word on the front of the second word’: a type of paraphasia also called a ‘spoonerism’ (eg, ‘belly jeans’ for ‘jelly beans’.)

Fourteen patients reported symptoms that ‘come and go’, but 23 (47%) reported distinct remissions during which their normal accent returned for hours to days. Tiredness, stress and migraine were frequent exacerbating factors; rest and relaxation frequent relieving factors. Most believed that symptoms were caused by ‘neurological disease like stroke’ (30) or ‘damage to the nervous system’ (26) although several did not believe symptoms were caused by disease (9) or damage (8). A significant proportion endorsed ‘stress or worry’ (16) as a cause of symptoms.

Fifteen (31%) agreed that they had developed national characteristics which they associated with their accent: hand movements (9), changes in syntax (‘like Pidgeon (sic) English’, ‘like a foreigner learning English’), vocabulary (‘instead of saying yes, saying ja ja’, and interpersonal behaviour (‘…become loud, arrogant and sneering’). One described using appropriate slang words so as to ‘fit the part’.

Comorbidities

Other symptoms included memory problems (42), limb weakness (31), daily pain in more than one part of the body (28) and tremor or abnormal limb movements (26). There were mild anxiety symptoms in the group overall, with moderate-severe anxiety in 11 and moderate-severe depressive symptoms in 8 (table 2).

Table 2

Comorbidities and social and occupational function

Auditory-perceptual analysis

Eleven of the 13 cases for which an audio(visual) recording was provided were classified after blinded auditory-perceptual analysis in agreement with the consensus classification above. For two classification was uncertain. Both blinded independent raters were in full agreement regarding allocation to ‘probably functional’, ‘possibly structural’, ‘probably structural’ or ‘uncertain’. Those categorised as ‘probably functional’ had speech and/or voice and/or language behaviours that did not fit diagnostic features for dysarthria, apraxia of speech, dysprosody or aphasia; inconsistencies were present (table 3). A selection of recorded speech samples from four participants and commentary on our analysis of these recordings are included as online supplementary files (online supplementary notes, Recording A Task A, Recording A Task B, Recording B Task A, Recording B Task B, Recording C Task A, Recording C Task B, Recording D Task A, Recording D Task B).

Table 3

Examples of language, speech, voice and prosody changes suggesting classification as functional or structural disease aetiology (link to annotated recordings)

Discussion

In this study of a large cohort of people self-reporting FAS, the majority (71%) were considered likely to have a functional aetiology.

Identifying features which can indicate functional FAS with more certainty would help in developing treatments and reducing iatrogenic harm. The auditory-perceptual framework employed here for classification of speech-voice-language deviations was able to highlight positive clinical features of functional FAS, showing mismatches across levels of analysis (voice, speech, etc) not compatible with expected findings for structural disorders. This framework might usefully be tested for diagnostic value in a validated clinical sample. The three speech behaviours that appeared to most strongly associated with a diagnosis of functional FAS (table 3) concerned: (1) where there was a mismatch between the apparent speech difficulties and the underlying physical assessment (eg, problems with tongue tip sounds but no evidence of tongue tip weakness, incoordination or apraxia of speech that might account for this); (2) inconsistency in occurrence of a speech change not linked to well-recognised variables such as syllable complexity (‘l’ sound in ‘lane’ vs ‘explain’) or phonotactic probability (likelihood of one sound following another; ‘asked’ vs ‘axed’); (3) presence of speech changes not found in neurological motor speech disorders (eg, infantile prosody; intrusion of foreign words—‘garden is bella’; ‘parents’ pronounced as a French word even though all surrounding words have an English accent).

However, some features suggested by Lee et al 1 as evidence of functional FAS did not discriminate ‘probably functional’ from ‘probably structural’ FAS in this sample, occurring at a similar frequency in both groups: periods of remission (indicating inconsistency) (51% vs 40%); characteristics in keeping with a stereotype associated with the accent (34% vs 30%) and ability to copy other accents (20% vs 10%) .

Structural FAS may occur in connection with lesions of pathways contributing to well-understood speech motor control networks (basal ganglia; cerebellum; thalamus; primary and secondary motor cortex, insula and their interconnections, eg, thalamocortical, cerebellar-cortical tracts), predominantly in the left/dominant hemisphere, though prosodic disturbance may be associated with right hemisphere lesions.12 Structural FAS is less likely where there is no visible structural lesion; where the lesion is at a site unlikely to disrupt speech motor control; or where the speech changes are not compatible in their nature or consistency with the pattern expected from a lesion at the particular site. We propose that features of functional FAS can occur in those with structural lesions because FAS may in some cases have a functional basis even when it starts after neurological injury. This is supported by wider observations. In our clinical experience, most who develop FAS after neurological injury recover within weeks. While acoustic and physiological speech changes may persist, the period of sounding ‘foreign’ is typically short. It seems likely that, where FAS persists, a functional disorder is largely responsible for a chronic change in accent.

The frequency of physically or psychologically noxious events at symptom onset was striking and may have pathophysiological significance paralleling other functional disorders such as persistent postural-perceptual dizziness after vestibular disturbance or functional limb weakness after physical injury.13 14 Recent research has examined the role of attention in functional symptoms.15 Here, perhaps transient changes in awareness or perception following facial injury, migraine, stroke, functional disorder presenting similarly to a stroke, or dissociative seizure produce abnormal attentional focus on the voice or mechanics of speech, disrupting normally automatic speech processes.16

Our analyses also help to clarify the extent to which FAS may be considered a disturbance of prosody. The perception of FAS has been associated with the presence of both segmental speech changes (ie, changes to individual sounds, eg, ‘sh’ sounds like ‘s’, sheet → seat, ‘i’ sounds like ‘ee’, ship → sheep) and suprasegmental/prosodic changes (eg, alterations to speech rhythm, stress placement in words and sentences, intonation pattern). Reports of an isolated dysprosody have appeared, starting with Monrad-Krohn’s classic study.17 However, our analysis here supports a view that altered prosody is not the sole trigger for perceived foreign accent. In keeping with the majority of reports of FAS, the speakers in the present cohort evidenced features of segmental and suprasegmental alterations. There were none with a solely prosodic disturbance.

The self-reported nature of these data prevents confident conclusions about aetiology. Selection bias is also likely: some individuals with self-reported FAS may strongly identify with this diagnosis and yet not necessarily be classified by naïve listeners as having a foreign accent, though it might usually be agreed that they have a different accent to their previous habitual speech; they may be influenced by experiences shared by other support group members; all were English speaking and the online survey precluded significant cognitive difficulties.

Nevertheless, this study reporting the largest series of FAS cases to date generates an important hypothesis: that FAS may often be an FND, whether a structural neurological lesion is present or not.

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References

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Footnotes

  • Contributors LM designed the study, collected the data, analysed the data and prepared and revised the manuscript. NM designed the study, analysed and reported the audio data and revised the manuscript. CC drafted the manuscript. IH designed the study and drafted the survey. AL collected the audio recording data. AC designed the study, interpreted the data and revised the manuscript for intellectual content. JS designed the study, interpreted the data and revised the manuscript for intellectual content.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests LM is undertaking a research fellowship funded philanthropically by Baillie Gifford. IH is supported by and ABN/Patrick Berthoud Charitable Trust Research Training Fellowship. AC is a paid editor of the Journal of Neurology, Neurosurgery and Psychiatry. He is a director of a limited personal services company that provides independent medical testimony in court cases on a range of neuropsychiatric topics on a 50% pursuer 50% defender basis. JS is a Chief Scientists Office NHS Research Scotland Career Researcher. JS provides independent medical testimony in court cases regarding patients with functional disorders.

  • Patient consent for publication Obtained.

  • Ethics approval The study received NHS Ethical approval.

  • Provenance and peer review Not commissioned; externally peer reviewed.

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