Motor speech patterns in Huntington disease.

OBJECTIVE: Dysarthric speech of persons with Huntington disease (HD) is typically described as hyperkinetic; however, studies suggest that dysarthria can vary and resemble patterns in other neurologic conditions. To test the hypothesis that distinct motor speech subgroups can be identified within a larger cohort of patients with HD, we performed a cluster analysis on speech perceptual characteristics of patient audio recordings. METHODS: Audio recordings of 48 patients with mild to moderate dysarthria due to HD were presented to 6 trained raters. Raters provided scores for various speech features (e.g., voice, articulation, prosody) of audio recordings using the classic Mayo Clinic dysarthria rating scale. Scores were submitted to an unsupervised k-means cluster analysis to determine the most salient speech features of subgroups based on motor speech patterns. RESULTS: Four unique subgroups emerged from the cohort of patients with HD. Subgroup 1 was characterized by an abnormally fast speaking rate among other unique speech features, whereas subgroups 2 and 3 were defined by an abnormally slow speaking rate. Salient speech features for subgroup 2 overlapped with subgroup 3; however, the severity of dysarthria differed. Subgroup 4 was characterized by mild deviations of speech features with typical speech rate. Length of CAG repeats, Unified Huntington's Disease Rating Scale total motor score, and percent intelligibility were significantly different for pairwise comparisons of subgroups. CONCLUSION: This study supports the existence of distinct presentations of dysarthria in patients with HD, which may be due to divergent pathologic processes. The findings are discussed in relation to previous literature and clinical implications.

A modified multimodal communication treatment for individuals with traumatic brain injury.

People living with the effects of traumatic brain injury (TBI) might use augmentative and alternative communication (AAC) due to cognitive-communication disabilities and/or co-occurring motor speech disorders. However, the most effective method for teaching people with TBI to use AAC strategies and resolve communication breakdowns is unknown. Prior research conducted with people with aphasia suggests an integrated multimodal treatment improved the use of AAC to resolve communication breakdowns. In this study, the researchers measured the effectiveness of a modified Multimodal Communication Treatment designed to increase communication breakdown resolution and use of AAC strategies by two individuals with TBI. A multiple baseline, single-case design was used to measure outcomes for the two participants who had motor speech disorders and cognitive-communication impairments. They completed four pre-treatment sessions, 20 treatment sessions, and three post-treatment sessions. Dependent variables included the number of AAC strategies produced during a modality probe task and two measures of communication breakdown resolution during a structured, functional task. Both participants increased use of AAC strategies during modality probes, but demonstrated minimal changes in communication breakdown resolution variables, potentially due to their impairments in executive function and memory. Results indicate that modifications to MCT may improve the use of AAC strategies for communication breakdown resolution for some people with TBI.