Purpose Standardized clinical assessment of dysarthria is essential for management and research. We present a new, fully standardized dysarthria assessment, the Bogenhausen Dysarthria Scales (BoDyS). The measurement model of the BoDyS is based on auditory evaluations of connected speech using 9 scales (traits) assessed by 4 elicitation methods. Analyses of the BoDyS' reliability and construct validity were performed to test this model, with the aim of gauging the auditory dimensions of speech impairment in dysarthria. Method Interrater agreement was examined in 70 persons with dysarthria. Construct validity was examined in 190 persons with dysarthria using a multitrait-multimethod design with confirmatory factor analysis. Results Interrater agreement of < 1 on a 5-point scale was found in 91% of cases across listener pairs and scales. Average reliability was .85. Inspection of the multitrait-multimethod matrix pointed at a high convergent and discriminant validity. Modeling of the BoDyS trait and method factors using confirmatory factor analysis yielded high goodness of fit. Model coefficients confirmed high discriminant and convergent validity and revealed meaningful relationships between scales and methods. Conclusions The 9 auditory scales of the BoDyS provide a reliable and valid profile of dysarthric impairment. They permit standardized measurement of clinically relevant dimensions of dysarthric speech.
The aim of this article is to explicate the uniqueness of the motor activity implied in spoken language production and to emphasize how important it is, from a theoretical and a clinical perspective, to consider the motor events associated with speaking as domain-specific, i.e., as pertaining to the domain of linguistic expression. First, phylogenetic data are reviewed demonstrating the specificity of the human vocal tract motor network regarding (i) the entrenchment of laryngeal motor skills within the organization of vocal tract movements, (ii) the evolution of a neural basis for skill acquisition within this system, and (iii) the integration of this system into an auditory-motor network. Second, ontogenetic evidence and existing knowledge about the experience-dependent plasticity of the brain are reported to explicate that during speech acquisition the vocal tract motor system is constrained by universal properties of speech production and by the specific phonological properties of the speaker's ambient language. Third, clinical data from dysarthria and apraxia of speech provide the background for a discussion about the theoretical underpinnings of domain-general versus domain-specific views of speech motor control. The article ends with a brief sketch of a holistic neurophonetic approach in experimental inquiries, assessment, and treatment of neuromotor speech impairment.
1 July 2021 in Journal of Speech, Language, and Hearing Research
Purpose: This article describes the developmental trajectories of four communication-related parameters (i.e., intelligibility, articulation rate, fluency, and communicative efficiency) in a cross-sectional study of typically developing children between 3 and 9 years. The four target parameters were related to auditory-perceptual parameters of speech function. Method: One hundred forty-four typically developing children (ages 3; 0-9;11 [years; months]; 72 girls and 72 boys) participated. Speech samples were collected using the materials of the Bogenhausen Dysarthria Scales for Childhood Dysarthria, a German assessment tool for childhood dysarthria, and analyzed following established auditory-perceptual criteria on relevant speech functions. To assess intelligibility, naive listeners transcribed sentences repeated by the children. Articulation rate and fluency were measured by acoustic analyses; communicative efficiency was determined by multiplying the proportion of correctly transcribed syllables by speech rate. Results: Intelligibility showed a steep developmental trajectory, with the majority of children obtaining a proportion Articulation rate demonstrated a flatter trajectory, with high variability still within the older children. Disfluencies, on the contrary, occurred only in the youngest children. By definition, communicative efficiency shared the characteristics of intelligibility and rate curves. A principal component analysis revealed, among other findings, strong connections between intelligibility and articulation, as well as between communicative efficiency, articulation, and rate measures. Conclusions: While children speak intelligibly, in terms of the applied assessment, at a comparably young age, other communication-relevant parameters show a slower developmental progress. Knowledge on the typical development of communication-related parameters and on their complex relationships with functional speech variables is crucial for the clinical assessment of childhood dysarthria.