Speech and Nonspeech Parameters in the Clinical Assessment of Dysarthria: A Dimensional Analysis

Abstract

Nonspeech (or paraspeech) parameters are widely used in clinical assessment of speech impairment in persons with dysarthria (PWD). Virtually every standard clinical instrument used in dysarthria diagnostics includes nonspeech parameters, often in considerable numbers. While theoretical considerations have challenged the validity of these measures as markers of speech impairment, only a few studies have directly examined their relationship to speech parameters on a broader scale. This study was designed to investigate how nonspeech parameters commonly used in clinical dysarthria assessment relate to speech characteristics of dysarthria in individuals with movement disorders. Maximum syllable repetition rates, accuracies, and rates of isolated and repetitive nonspeech oral–facial movements and maximum phonation times were compared with auditory–perceptual and acoustic speech parameters. Overall, 23 diagnostic parameters were assessed in a sample of 130 patients with movement disorders of six etiologies. Each variable was standardized for its distribution and for age and sex effects in 130 neurotypical speakers. Exploratory Graph Analysis (EGA) and Confirmatory Factor Analysis (CFA) were used to examine the factor structure underlying the diagnostic parameters. In the first analysis, we tested the hypothesis that nonspeech parameters combine with speech parameters within diagnostic dimensions representing domain–general motor control principles. In a second analysis, we tested the more specific hypotheses that diagnostic parameters split along effector (lip vs. tongue) or functional (speed vs. accuracy) rather than task boundaries. Our findings contradict the view that nonspeech parameters currently used in dysarthria diagnostics are congruent with diagnostic measures of speech characteristics in PWD.

Objective assessment of dysarthric disorders in patients with multiple sclerosis depending on sex, age, and type of text read

“…A review of the literature focusing on the issues shows that research evaluating the character of speech disorders in MS is limited (15,23). The available dysarthria scales are based on more or less subjective data, which are more difficult to compare (15,(18)(19)(20)(21)(22)(23). As noted in the review article by Noffs et al objective speech assessment is more accurate, replicable, and feasible when contrasted with perceptual analysis (25) which occurs in the majority of the studies concerning the notion of dysarthria in the course of neurological diseases.…”

“…The Speech Pathology Specific Questionnaire for people with MS has also been developed and validated (7). Based on the review of the world literature, it can be concluded that in many countries the following scales are most often used in phoniatric practice: Vocal Tract Discomfort, GRBAS listening scale, Voice Handicap Index (18)(19)(20)(21). All of the above-mentioned scales are subjective tools, and therefore they are burdened with a certain margin of error, thirdly, they do not allow for the unequivocal distinction between physiological and pathological values, therefore they are of limited use in routine clinical examinations of the vocal organ and do not accentuate on the mechanisms inducing the phenomenon of dysarthria, which is crucial in conducting therapy (22).…”

Functional Brain Connectivity Differences between Aphasic and Neurotypical Brains

“…Time's influence on lexical and syntactic processing in individuals with aphasia was explored [14]. The use of dimensional analysis to assess dysarthria highlights its importance for a nuanced evaluation of the speech disorder [15]. The study investigated the link between verbal short-term memory deficits in aphasic individuals and word processing impairments.…”

Detection of Subclinical Motor Speech Deficits after Presumed Low-Grade Glioma Surgery

“…Although widely used in motor speech assessments, DDK is still a subject of debate. Some studies propose that there is insufficient empirical evidence that would support the clinical use of nonspeech parameters in analyzing motor speech in patients with neurological disorders [23], while others suggest that DDK performance mirrors speech proficiency [24].…”