Data-Driven Classification of Dysarthria Profiles in Children With Cerebral Palsy

Abstract

Purpose: The objectives of this study were to examine different speech profiles among children with dysarthria secondary to cerebral palsy (CP) and to characterize the effect of different speech profiles on intelligibility.

Method: Twenty 5-year-old children with dysarthria secondary to CP and 20 typically developing children were included in this study. Six acoustic and perceptual speech measures were selected to quantify a range of segmental and suprasegmental speech characteristics and were measured from children's sentence productions. Hierarchical cluster analysis was used to identify naturally occurring subgroups of children who had similar profiles of speech features.

Results: Results revealed 4 naturally occurring speech clusters among children: 1 cluster of children with typical development and 3 clusters of children with dysarthria secondary to CP. Two of the 3 dysarthria clusters had statistically equivalent intelligibility levels but significantly differed in articulation rate and degree of hypernasality.

Conclusion: This study provides initial evidence that different speech profiles exist among 5-year-old children with dysarthria secondary to CP, even among children with similar intelligibility levels, suggesting the potential for developing a pediatric dysarthria classification system that could be used to stratify children with dysarthria into meaningful subgroups for studying speech motor development and efficacy of interventions.

Figure 1.

Example measurement of closure interval voicing associated with /p/ in the production of the word “happy” in a typically developing child.

Figure 2.

Dendogram showing the progressive linking of children based on similarity in speech features.

Figure 3.

Profiles of the borderline, Dysarthria 1 (DYS1), and Dysarthria 2 (DYS2) clusters on each of the acoustic and perceptual speech measures. z Scores are based on the mean and standard deviation of the typically developing children. Prop. = proportion of.

Figure 4.

Scatter plots showing the relation between intelligibility and articulation rate (top panel) and intelligibility and nasality rating (bottom panel) for children classified in each of the four clusters. DYS1 = Dysarthria 1; DYS2 = Dysarthria 2; TD = typically developing; syll/sec = syllables per second.