Friedreich ataxia (FRDA) is the most frequent recessive ataxia in the Western world. Dysarthria is a cardinal feature of FRDA, often leading to severe impairments in daily functioning, but its exact characteristics are only poorly understood so far. We performed a comprehensive evaluation of dysarthria severity and the profile of speech motor deficits in 20 patients with a genetic diagnosis of FRDA based on a carefully selected battery of speaking tasks and two widely used paraspeech tasks, i.e., oral diadochokinesis and sustained vowel productions. Perceptual ratings of the speech samples identified respiration, voice quality, voice instability, articulation, and tempo as the most affected speech dimensions. Whereas vocal instability predicted ataxia severity, tempo turned out as a significant correlate of disease duration. Furthermore, articulation predicted the overall intelligibility score as determined by a systematic speech pathology assessment tool. In contrast, neurologists’ ratings of intelligibility—a component of the “Scale for the Assessment and Rating of Ataxia”—were found to be related to perceived speech tempo. Obviously, clinicians are more sensitive to slowness of speech than to any other feature of spoken language during dysarthria evaluation. Our results suggest that different components of speech production and trunk/limb motor functions are differentially susceptible to FRDA pathology. Furthermore, evidence emerged that paraspeech tasks do not allow for an adequate scaling of speech deficits in FRDA.
This is a preview of subscription content, log in to check access
We would like to express our appreciation to the participants of this study for their willingness to support this research. This study was funded by the German Research Foundation (DFG; AC55/6-3; Zi469/10-3).
Conflicts of Interest
The authors of this manuscript do not have any conflicts of interest
Bhidayasiri R, Perlman SL, Pulst SM, Geschwind DH. Late-onset Friedreich ataxia. Phenotypic analysis, magnetic resonance imaging findings, and review of the literature. Arch Neurol. 2005;62:1865–9.PubMedCrossRefGoogle Scholar
Della Nave R, Ginestroni A, Giannelli M, et al. Brain structural damage in Friedreich’s ataxia. J Neurol Neurosurg Psychiatry. 2008;79:82–5.PubMedCrossRefGoogle Scholar
Della Nave R, Ginestroni A, Tessa C, et al. Brain white matter tracts degeneration in Friedreich ataxia: an in vivo MRI study using tract-based spatial statistics and voxel-based morphometry. NeuroImage. 2008;40:19–25.PubMedCrossRefGoogle Scholar
Synofzik M, Godau J, Lindig T, et al. Transcranial sonography reveals cerebellar, nigral, and forebrain abnormalities in Friedreich’s ataxia. Neurodegener Dis. 2011;8:470–5.PubMedCrossRefGoogle Scholar
Koeppen AH, Davis AN, Morral JA. The cerebellar component of Friedreich's ataxia. Acta Neuropathol. 2011;122:323–30.PubMedCrossRefGoogle Scholar
Harding AE. Friedreich’s ataxia: a clinical and genetic study of 90 families with an analysis of early diagnostic criteria and intrafamilial clustering of clinical features. Brain. 1981;104:589–620.PubMedCrossRefGoogle Scholar
Folker JE, Murdoch BE, Cahill LM, et al. Dysarthria in Friedreich’s ataxia: a perceptual analysis. Folia Phoniatr Logop. 2010;62:97–103.PubMedCrossRefGoogle Scholar
Singh A, Epstein E, Myers LM, et al. Clinical measures of dysarthria in Friedreich’s ataxia. Mov Disord. 2010;25:108–11.PubMedCrossRefGoogle Scholar
Eigentler A, Rhomberg J, Nachbauer W, et al. The scale for the assessment and rating of ataxia correlates with dysarthria assessment in Friedreich’s ataxia. J Neurol. 2012;259:420–6.PubMedCrossRefGoogle Scholar
Ackermann H, Hertrich I. Dysarthria in Friedreich’s ataxia: timing of speech segments. Clin Linguist Phonet. 1993;7:75–91.CrossRefGoogle Scholar
Ackermann H, Hertrich I. Speech rate and rhythm in cerebellar dysarthria—an acoustic analysis of syllabic timing. Folia Phoniatr Logop. 1994;46:70–8.PubMedCrossRefGoogle Scholar
Ziegler W, Wessel K. Speech timing in ataxic disorders: sentence production and rapid repetitive articulation. Neurology. 1996;47:208–14.PubMedCrossRefGoogle Scholar
Folker JE, Murdoch BE, Cahill LM, et al. Kinematic analysis of lingual movements during consonant productions in dysarthric speakers with Friedreich’s ataxia: a case-by-case analysis. Clin Linguist Phonet. 2011;25:66–79.CrossRefGoogle Scholar
Synofzik M, Srulijes K, Godau J, et al. Characterizing POLG ataxia: clinics, electrophysiology and imaging. Cerebellum. 2012. doi:10.1007/s12311-012-0378-2.
Ziegler W. Speech motor control is task-specific. Evidence from dysarthria and apraxia of speech. Aphasiology. 2003;17:3–36.CrossRefGoogle Scholar
Bunton K. Speech versus nonspeech: different tasks. Different neural organization. Semin Speech Lang. 2008;29:267–75.PubMedCrossRefGoogle Scholar
Ziegler W. Task-related factors in oral motor control: speech and oral diadochokinesis in dysarthria and apraxia of speech. Brain Lang. 2002;80:556–75.PubMedCrossRefGoogle Scholar