Age Estimation and Gender Attribution in Typically Developing Children and Children With Dysarthria.

PURPOSE: The purposes of this study were (a) to investigate adult listeners' perceptions of age and gender in typically developing children and children with dysarthria and (b) to identify predictors of their estimates among auditory-perceptual parameters and an acoustic measure of vocal pitch (F0). We aimed to evaluate the influence of dysarthria on the listeners' impressions of age and gender against the background of typical developmental processes. METHOD: In a listening experiment, adult listeners completed age and gender estimates of 144 typically developing children (3-9 years of age) and 25 children with dysarthria (5-9 years of age). The Bogenhausen Dysarthria Scales for Childhood Dysarthria (BoDyS-KiD) were applied to record speech samples and to complete auditory-perceptual judgments covering all speech subsystems. Furthermore, each child's mean F0 was determined from samples of four BoDyS-KiD sentences. RESULTS: Age estimates for the typically developing children showed a regression to the mean, whereas children with dysarthria were systematically underestimated in their age. The estimates of all children were predicted by developmental speech features; for the children with dysarthria, specific dysarthria symptoms had an additional effect. We found a significantly higher accuracy of gender attribution in the typically developing children than in the children with dysarthria. The prediction accuracy of the listeners' gender attribution in the preadolescent children by the included speech characteristics was limited. CONCLUSIONS: Children with dysarthria are more difficult to estimate for their age and gender than their typically developing peers. Dysarthria thus alters the auditory-perceptual impression of indexical speech features in children, which must be considered another facet of the communication disorder associated with childhood dysarthria.

Clinical Practice in Childhood Dysarthria: An Online Survey of German-Speaking Speech-Language Pathologists.

PURPOSE: This survey study aimed to establish current clinical practices of German-speaking speech-language pathologists (SLPs) regarding their assessment and treatment of communication disorders in children with neurological conditions, with a particular focus on the management of childhood dysarthria. METHOD: A 23-question cross-sectional online survey was disseminated to practicing SLPs in Germany, Austria, and Switzerland via relevant professional bodies. SLPs were invited to provide information on their current assessment and treatment practices. Demographic data including case load and clinical settings were also gathered to contextualize practices. RESULTS: One hundred two SLPs responded to the survey, of which 68 valid responses were analyzed. German-speaking SLPs comprehensively assess and treat various aspects of overall communication, language, and swallowing functions in children with neurological conditions. Speech motor aspects did not represent a main intervention focus. In cases where the dysarthric component was targeted, specific approaches for childhood dysarthria were rarely used. Instead, SLPs reported using approaches developed for speech disorders other than dysarthria. CONCLUSIONS: German-speaking SLPs working with children with neurological conditions use various assessment and treatment methods to support children's communication. However, dysarthria-specific approaches were not an established part of clinical practice. Results of the survey highlight the need for access to relevant developments in German and for evaluation of current curricula for speech-language pathology students and continuing education opportunities for practicing clinicians.

Speech Naturalness in the Assessment of Childhood Dysarthria.

PURPOSE: This study investigated perceived speech naturalness estimated by adult listeners in typically developing children and children with dysarthria. We aimed to identify predictors of naturalness among auditory-perceptual parameters and to evaluate the concept of naturalness as a clinical marker of childhood dysarthria. METHOD: In a listening experiment, naive adult listeners rated speech naturalness of 144 typically developing children (3-9 years old) and 28 children with neurological conditions (5-9 years old) on a visual analog scale. Speech samples were recorded using the materials of the Bogenhausen Dysarthria Scales-Childhood Dysarthria, which also provides for auditory-perceptual judgments covering all speech subsystems. RESULTS: Children with dysarthria obtained significantly lower naturalness ratings compared to typically developing children. However, there was a substantial age effect observable in the typically developing children; that is, younger typically developing children were also perceived as somewhat unnatural. The ratings of the typically developing children were influenced by the occurrence of developmental speech features; for the children with neurological conditions, specific symptoms of dysarthria had an additional effect. In both groups, the perception of naturalness was predominantly determined by the children's articulation and intelligibility. CONCLUSIONS: Both symptoms of childhood dysarthria and developmental speech features (e.g., regarding articulation and intelligibility) were associated to some extent with unnatural speech by the listeners. Thus, perceived speech naturalness appears less suitable as a marker of dysarthria in children than in adults.

Speech Motor Profiles in Primary Progressive Aphasia.

PURPOSE: Previous research on motor speech disorders (MSDs) in primary progressive aphasia (PPA) has largely focused on patients with the nonfluent/agrammatic variant of PPA (nfvPPA), with few systematic descriptions of MSDs in variants other than nfvPPA. There has also been an emphasis on studying apraxia of speech, whereas less is known about dysarthria or other forms of MSDs. This study aimed to examine the qualitative and quantitative characteristics of MSDs in a prospective sample of individuals with PPA independent of subtype. METHOD: We included 38 participants with a root diagnosis of PPA according to current consensus criteria, including one case with primary progressive apraxia of speech. Speech tasks comprised various speech modalities and levels of complexity. Expert raters used a novel protocol for auditory speech analyses covering all major dimensions of speech. RESULTS: Of the participants, 47.4% presented with some form of MSD. Individual speech motor profiles varied widely with respect to the different speech dimensions. Besides apraxia of speech, we observed different dysarthria syndromes, special forms of MSDs (e.g., neurogenic stuttering), and mixed forms. Degrees of severity ranged from mild to severe. We also observed MSDs in patients whose speech and language profiles were incompatible with nfvPPA. CONCLUSIONS: The results confirm that MSDs are common in PPA and can manifest in different syndromes. The findings emphasize that future studies of MSDs in PPA should be extended to all clinical variants and should take into account the qualitative characteristics of motor speech dysfunction across speech dimensions. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.22555534.

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

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.

Profiles of Dysarthria: Clinical Assessment and Treatment.

In recent decades, we have witnessed a wealth of theoretical work and proof-of-principle studies on dysarthria, including descriptions and classifications of dysarthric speech patterns, new and refined assessment methods, and innovative experimental intervention trials [...].

Intelligibility, Speech Rate, and Communication Efficiency in Children With Neurological Conditions: A Longitudinal Study of Childhood Dysarthria.

PURPOSE: This study aimed to describe communication-related parameters (i.e., intelligibility, speech rate, and communication efficiency) and their developmental courses in children with neurological conditions against the background of typical development. In addition, interrelations between the developmental courses of communication-related parameters and auditory-perceptual ratings related to speech subsystems were investigated. METHOD: Fourteen children with neurological conditions (CNC) and 14 typically developing children (CTD), matched for age and gender (four girls; 5;1-8;4 [years;months] at first examination), were assessed at three points in time over an 18-month period. Speech samples were collected using the Bogenhausener Dysarthrie Skalen-Kindliche Dysarthrien (English: Bogenhausen Dysarthria Scales-Childhood Dysarthria), a German tool for the assessment of childhood dysarthria. To assess intelligibility, naïve listeners transcribed audio samples of sentence repetitions of the children. Speech rate was measured by acoustic analyses, and communication efficiency was determined by multiplying the proportion of correctly transcribed syllables with speech rate. Age normalization was performed following a recently published approach. RESULTS: On the group level, CNC had conspicuous raw and normalized scores for the three communication-related parameters and were more variable than the CTD group regarding their developmental courses. These differences were more pronounced for intelligibility than for speech rate. A strong relationship between communication-related and speech subsystems-related auditory-perceptual characteristics was apparent only between intelligibility and articulation/resonance. CONCLUSIONS: For the first time, age-normalized scores for communication-related parameters were reported in children with neurological disorders and put into a developmental context within the framework of a longitudinal study. Age-normalized intelligibility was more vulnerable to large developmental changes than speech rate and was best predicted by changes in articulation and resonance. Overall, this study may contribute to a more comprehensive and valid clinical assessment of childhood dysarthria and to a better understanding of its developmental dynamics.

Childhood Dysarthria: Auditory-Perceptual Profiles Against the Background of Typical Speech Motor Development.

PURPOSE: The purpose of this study was to describe childhood dysarthria by means of auditory-perceptual analyses covering all speech subsystems. We aimed to identify the most seriously affected auditory-perceptual dimensions in the observed dysarthria profiles and to detect specific markers of childhood dysarthria against the backdrop of typical speech development. Moreover, the relationship between the speech disorder and other relevant aspects of multiple disability was investigated. METHOD: Thirty-one children with neurologic conditions were assessed with Bogenhausen Dysarthria Scales for Childhood Dysarthria, a German tool for the auditory-perceptual analysis of dysarthria in children. Nine relevant speech dimensions (scales, e.g., voice quality [VOQ]) and 29 individual symptoms (features, e.g., breathy) were evaluated. Moreover, we documented motor, communicative, and cognitive-linguistic measures (i.e., Gross Motor Function Classification System [GMFCS], Communication Function Classification System [CFCS], Test for Reception of Grammar [TROG-D], and memory span). Recently published data from typically developing children were used for the purpose of age normalization. RESULTS: Dysarthria severity was moderately correlated with GMFCS and CFCS but not with TROG-D and memory span. At the group level, respiration, articulation, and prosodic modulation were most severely affected, whereas voice function was only mildly affected or even spared in the majority of children. Four features were identified as most relevant markers of childhood dysarthria: conspicuous rhythm/stress pattern, hypernasality, strained-strangled voice, and reduced articulatory precision. CONCLUSIONS: Childhood dysarthria is part of a complex multiple disability, but speech motor skills may still dissociate from gross-motor and cognitive-linguistic functions. Auditory-perceptual analyses incorporating age norms allow for a comprehensive description and identification of childhood dysarthria.

Intelligibility, Articulation Rate, Fluency, and Communicative Efficiency in Typically Developing Children.

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, naïve 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 of intelligible syllables close to 1.0 at the age of 5 years. 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. Supplemental Material https://doi.org/10.23641/asha.14880285.

Motor speech disorders in the nonfluent, semantic and logopenic variants of primary progressive aphasia.

OBJECTIVE: Motor speech disorders (MSDs) are characteristic for nonfluent primary progressive aphasia (nfvPPA). In primary progressive aphasia (PPA) of the semantic (svPPA) and of the logopenic type (lvPPA), speech motor function is considered typically intact. However, knowledge on the prevalence of MSDs in svPPA and lvPPA is mainly based on studies with a priori knowledge of PPA syndrome diagnosis. This fully blinded retrospective study aims to provide data on the prevalence of all types of MSDs in a large sample of German-speaking patients with different subtypes of PPA. METHOD: Two raters, blinded for PPA subtype, independently evaluated connected speech samples for MSD syndrome and severity from 161 patients diagnosed with nfvPPA, svPPA or lvPPA in the database of the German Consortium of Frontotemporal Lobar Degeneration (FTLDc). In case of disagreement, a third experienced rater re-evaluated the speech samples, followed by a consensus procedure. Consensus was reached for 160 patients (74 nfvPPA, 49 svPPA, 37 lvPPA). MAIN RESULTS: Across all PPA syndromes, 43.8% of the patients showed MSDs. Patients with nfvPPA demonstrated the highest proportion of MSDs (62.2%), but MSDs were also identified in svPPA (26.5%) and lvPPA (29.7%), respectively. Overall, dysarthria was the most common class of MSDs, followed by apraxia of speech. In addition, we identified speech abnormalities presenting as "syllabic speech", "dysfluent speech", and "adynamic speech". DISCUSSION: Our study confirmed MSDs as frequently occurring in PPA. The study also confirmed MSDs to be most common in patients with nfvPPA. However, MSDs were also found in substantial proportions of patients with svPPA and lvPPA. Furthermore, our study identified speech motor deficits that have not received attention in previous studies on PPA. The results are discussed against the background of the existing literature on MSDs in PPA, including theoretical considerations of the neuroanatomical conditions described for each of the different subtypes of PPA.

Developmental Courses in Childhood Dysarthria: Longitudinal Analyses of Auditory-Perceptual Parameters.

Purpose The aim of this longitudinal study was to describe developmental courses of childhood dysarthria against the background of typical speech motor development by collecting auditory-perceptual data. Method Fourteen children (four girls, 10 boys; 5;1-8;4 [years;months] at Time 1) with neurological conditions (CNC) and 14 typically developing children (CTD) matched for age and gender were assessed at three points in time over an 18-month period. Speech samples were collected using the Bogenhausener Dysarthrie Skalen-Kindliche Dysarthrien (BoDyS-KiD; in English: Bogenhausen Dysarthria Scales-Childhood Dysarthria), a German tool for the assessment of childhood dysarthria, and analyzed by means of nine perceptual scales covering all clinically relevant speech components. Age normalization was performed according to a method published recently. Data from the matched controls were used to estimate whether the gradients of the CNC group's developmental trajectories exceeded those of typical development. Results The children with neurological conditions presented heterogeneous speech profiles with a wide range of severity. At the group level, relatively stable trajectories of the age-normalized dysarthria total score were found over the observation period. The nine perceptual scales showed more or less parallel developments. All patients except two followed the growth curve describing the developmental course of the typically developing children. Conclusions Most children took advantage of the developmental dynamics as they developed parallel to the age norm. With its comprehensive description of the developmental courses of 14 children with neurological conditions, this study may contribute to a more valid, statistically verified clinical assessment of the course of childhood dysarthria.

Dysarthria syndromes in children with cerebral palsy.

AIM: To investigate whether dysarthria syndromes acquired in adulthood can also be observed in children with cerebral palsy (CP) and, if so, whether they align with children's CP subtypes. METHOD: Twenty-six children with CP participated (mean age 7y 8mo [SD 1y 2mo], 5y 1mo-9y 10mo; 16 males and 10 females). Speech samples were elicited in a computer-based game and were analysed using the auditory perceptual criteria of the Bogenhausen Dysarthria Scales (BoDyS). For statistical classification, three comparison groups of adults with standard dysarthria syndromes (i.e. spastic, hyperkinetic, and ataxic) were used. Their BoDyS data were entered into a mixture discriminant analysis, with data from the comparison groups as the training sample and those from the children with CP as the test sample. Results were related to findings in a group of adults with CP. RESULTS: Among the children with CP, most had spastic (n=14), while fewer had ataxic (n=9) or hyperkinetic (n=3), dysarthria. However, syndrome allocations were significantly more ambiguous than in adults with CP. For 11 children, their dysarthria syndromes did not align with their CP subtype. INTERPRETATION: Dysarthria syndromes are less clear cut in children than in adults with CP because of a number of developmental factors. WHAT THIS PAPER ADDS: Children with cerebral palsy (CP) show diverse patterns of dysarthric symptoms. Dysarthria syndromes do not seem to manifest fully during childhood. Dysarthria syndrome and CP subtype may not align in children with CP.

Age Norms for Auditory-Perceptual Neurophonetic Parameters: A Prerequisite for the Assessment of Childhood Dysarthria.

Purpose The aim of this study was to collect auditory-perceptual data on established symptom categories of dysarthria from typically developing children between 3 and 9 years of age, for the purpose of creating age norms for dysarthria assessment. Method One hundred forty-four typically developing children (3;0-9;11 [years;months], 72 girls and 72 boys) participated. We used a computer-based game specifically designed for this study to elicit sentence repetitions and spontaneous speech samples. Speech recordings were analyzed using the auditory-perceptual criteria of the Bogenhausen Dysarthria Scales, a standardized German assessment tool for dysarthria in adults. The Bogenhausen Dysarthria Scales (scales and features) cover clinically relevant dimensions of speech and allow for an evaluation of well-established symptom categories of dysarthria. Results The typically developing children exhibited a number of speech characteristics overlapping with established symptom categories of dysarthria (e.g., breathy voice, frequent inspirations, reduced articulatory precision, decreased articulation rate). Substantial progress was observed between 3 and 9 years of age, but with different developmental trajectories across different dimensions. In several areas (e.g., respiration, voice quality), 9-year-olds still presented with salient developmental speech characteristics, while in other dimensions (e.g., prosodic modulation), features typically associated with dysarthria occurred only exceptionally, even in the 3-year-olds. Conclusions The acquisition of speech motor functions is a prolonged process not yet completed with 9 years. Various developmental influences (e.g., anatomic-physiological changes) shape children's speech specifically. Our findings are a first step toward establishing auditory-perceptual norms for dysarthria in children of kindergarten and elementary school age. Supplemental Material https://doi.org/10.23641/asha.12133380.

The Impact of Dysarthria on Laypersons' Attitudes towards Adults with Cerebral Palsy.

OBJECTIVE: This study investigated laypersons' attitudes towards adults with dysarthria due to cerebral palsy (CP). We aimed to explore the impact of the overall severity and of specific symptoms of dysarthria on laypersons' evaluations. PATIENTS AND METHODS: Eighteen adults with dysarthria due to CP and 6 nondysarthric controls participated as speakers. The individuals with CP underwent dysarthria assessment based on a standardized tool. The results were compared to those of a listening experiment with 20 laypersons. A text passage spoken by all speakers was presented to the listeners, who provided their evaluations using rating scales specifically developed for this study. The tool addressed 3 dimensions of attitudes: (1) estimation of a speaker's cognitive-linguistic abilities; (2) attribution of personality and social characteristics, and (3) listeners' emotions and behavioral tendencies towards the speaker. RESULTS: Severity of dysarthria was strongly correlated with the overall attitudes. Regression analyses identified different symptoms as predictors of the listeners' judgements. CONCLUSION: Severity of dysarthria seems to have a major impact on laypersons' attitudes. Results suggest that speech symptoms may have a very specific influence on laypersons' evaluations. This may be important for clinical care, since symptoms with the most negative impact should be focused on in treatment.

Higher-Faster-Farther: Maximum Performance Tests in the Assessment of Neurogenic Speech Impairment.

BACKGROUND: Maximum performance tests are widely used in dysarthria assessment. From a theoretical perspective, the motor demands of such tasks differ from those of speaking. Therefore, their validity as measures of dysarthric impairment needs to be established empirically. PATIENTS AND METHODS: Maximum phonation time (MPT) and maximum syllable repetition rate (MRR) were compared with sentence reading/repetition tasks. In study 1, 130 patients with neurologic movement disorders and 130 healthy control participants were examined. Presence/severity of dysarthria was measured using psychometrically standardized auditory scales. In study 2, 16 healthy volunteers participated in an experiment designed to examine the intraspeaker variability of MPT, MRR, and sentence repetition across eight trials. RESULTS: Study 1: MPT made no reasonable contribution to the diagnosis of dysarthria or of any specific dimension of perceived speech impairment. MRR correlated with overall speech impairment but turned out to be an insensitive and highly unspecific statistical marker, afflicted with aetiology-specific errors. Study 2: compared with sentence repetition, both MPT and MRR demonstrated highly increased within-subject inconsistencies. CONCLUSION: The validity of MPT and MRR tasks as measures of dysarthria is still unsettled.

The feasibility of assessing speech and non-speech function of the speech apparatus in adults with cerebral palsy.

This short note reports on observations concerning the feasibility of a set of speech and non-speech assessment tasks in an investigation of dysarthria in 21 adults (15 males/6 females; median 23 years) with cerebral palsy and concomitant cognitive impairment. The participants were assessed with nine tasks representing standard components of clinical dysarthria assessment (i.e. six speech and three non-speech tasks). The tasks were evaluated for their feasibility on the basis of common clinical criteria. Our results indicated that, overall, speech tasks were more feasible than non-speech tasks. Several participants showed signs of dysexecutive behaviour on some of the non-speech tasks, but not on the speech tasks. The current note provides tentative clues regarding the impact of cognitive deficits on the feasibility of assessment tasks in the diagnosis of dysarthria.

Gauging the Auditory Dimensions of Dysarthric Impairment: Reliability and Construct Validity of the Bogenhausen Dysarthria Scales (BoDyS).

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.

Dissociating oral motor capabilities: Evidence from patients with movement disorders.

Abnormal articulation rate is a frequent symptom in neurogenic speech disorders. Performance rates in speech-like or nonspeech tasks involving the vocal motor apparatus are commonly accepted predictors of speech motor function in general and of articulation rate in particular. However, theoretical arguments and behavioral observations in populations with disordered speech indicate that different oral motor behaviors may be governed by distinct mechanisms. The objective of the present study was to expand our knowledge of the relationship between speech movements, on the one hand, and speech-like and nonspeech oral motor behaviors, on the other, by using a rate paradigm. 130 patients with neurological movement disorders of different origins and 130 neurologically healthy subjects participated in the study. Rate data was collected in a speech task (oral reading/repetition), in speech-like tasks (rapid syllable repetitions), and in nonspeech tasks (rapid single articulator movements of the tongue/lips). The main analyses involved a multiple single-case method, by which we tested for differences among each patient's performance rates on the three task types. The results disclosed statistically significant (classical and strong) dissociations between movement rates obtained from the speech task and those obtained from speech-like and nonspeech oral motor tasks in a number of patients. The findings can be interpreted as reflecting major differences in task demands and underlying control mechanisms. The validity of diagnostic indices for speech obtained from speech-like or nonspeech tasks must thus be called into question.

Oral Motor Abilities Are Task Dependent: A Factor Analytic Approach to Performance Rate.

Measures of performance rates in speech-like or volitional nonspeech oral motor tasks are frequently used to draw inferences about articulation rate abnormalities in patients with neurologic movement disorders. The study objective was to investigate the structural relationship between rate measures of speech and of oral motor behaviors different from speech. A total of 130 patients with neurologic movement disorders and 130 healthy subjects participated in the study. Rate data was collected for oral reading (speech), rapid syllable repetition (speech-like), and rapid single articulator movements (nonspeech). The authors used factor analysis to determine whether the different rate variables reflect the same or distinct constructs. The behavioral data were most appropriately captured by a measurement model in which the different task types loaded onto separate latent variables. The data on oral motor performance rates show that speech tasks and oral motor tasks such as rapid syllable repetition or repetitive single articulator movements measure separate traits.