Syllable Repetition Task Research Articles

Rate-Related Kinematic Changes in Younger and Older Adults

Aims: This study aimed to investigate the effects of speech rate changes on kinematic characteristics and stability of speech movements in younger and older speakers using electromagnetic midsagittal articulography. Patients and Methods: Eight young adults and 8 older adults engaged in a series of syllable repetition tasks of /pa/, /sa/ and /ta/ obtained at self-paced slow, habitual and fast speech rates, as well as in a series of metronome-guided speech rates, ranging from 2 to 4 syllables per second. The kinematic parameters duration, amplitude and peak velocity were obtained for opening and closing movements. Results: Older speakers were able to increase speech rate to the same degree or higher compared to younger speakers in both pacing conditions. Kinematic data show that older adults increased duration and decreased peak velocity in closing movements of alveolar constrictions at slower rates more prominently than younger adults. The results on movement stability revealed no differences between age groups. Conclusions: The results suggest that an age-related difference in speed-accuracy trade-off can be ruled out. Differences in kinematic characteristics point towards the possibility that older adults aimed to facilitate a closed-loop control system to maintain movement stability at slower speech rates.

Impaired motor speech performance in Huntington’s disease

Dysarthria is a common symptom of Huntington's disease and has been reported, besides other features, to be characterized by alterations of speech rate and regularity. However, data on the specific pattern of motor speech impairment and their relationship to other motor and neuropsychological symptoms are sparse. Therefore, the aim of the present study was to describe and objectively analyse different speech parameters with special emphasis on the aspect of speech timing of connected speech and non-speech verbal utterances. 21 patients with manifest Huntington's disease and 21 age- and gender-matched healthy controls had to perform a reading task and several syllable repetition tasks. Computerized acoustic analysis of different variables for the measurement of speech rate and regularity generated a typical pattern of impaired motor speech performance with a reduction of speech rate, an increase of pauses and a marked disability to steadily repeat single syllables. Abnormalities of speech parameters were more pronounced in the subgroup of patients with Huntington's disease receiving antidopaminergic medication, but were also present in the drug-naïve patients. Speech rate related to connected speech and parameters of syllable repetition showed correlations to overall motor impairment, capacity of tapping in a quantitative motor assessment and some score of cognitive function. After these preliminary data, further investigations on patients in different stages of disease are warranted to survey if the analysis of speech and non-speech verbal utterances might be a helpful additional tool for the monitoring of functional disability in Huntington's disease.

Instability of syllable repetition in Parkinson's disease—Impairment of automated speech performance?

Steady vocal pace performance according to a multi-level syllable repetition paradigm has been previously shown to be compromised in patients in advanced stages of Parkinson's disease (PD) under chronic deep brain stimulation. The aim of the present study was to implement the same syllable repetition test in mildy to moderately affected patients in order to survey if (a) the characteristic pattern of abnormalities can be observed even in early stages of PD and (b) if there are correlations to motor symptoms of PD. Sixty-four patients with PD who were on stable dopaminergic medication and 40 healthy subjects had to repeat a single syllable (/pa/) or a pair of alternating syllables (/pa-ti/) in a self chosen steady pace or in a given pace of 80/min. As main results, PD patients’ pace performance was (1) already irregular in the simple steady syllable repetition task, (2) even more impaired when a given pace had to be kept and (3) showed a further decline when two alternating syllables had to be repeated in a given pace; (4) measures of irregular pace performance showed a correlation to axial motor symptoms. This pattern of impaired vocal pace performance was similar, although less pronounced, to the previously reported findings in advanced PD and therefore might be a characteristic feature of PD. The results could be interpreted as a hint for increasing disruption of automaticity in speech performance with rising complexity of the task which can be found even in early stages of PD and correlate to axial motor symptoms.

Lingual kinematics during rapid syllable repetition in Parkinson's disease

Rapid syllable repetition tasks are commonly used in the assessment of motor speech disorders. However, little is known about the articulatory kinematics during rapid syllable repetition in individuals with Parkinson's disease (PD). To investigate and compare lingual kinematics during rapid syllable repetition in dysarthric speakers with PD (DPD), non-dysarthric speakers with PD (NDPD) and a group of healthy controls. Electromagnetic articulography was used to record tongue-tip and tongue-back movement in five DPD and five NDPD participants during rapid repetition of /ta/and /ka/syllables, and matched with six healthy controls. Results revealed significant between-group differences for most of the kinematic parameters measured but comparable rapid syllable repetition rates. Post-hoc analyses indicated that the DPD participants, when compared with the NDPD participants, had similar range but prolonged duration of lingual movement. The DPD and NDPD participants had primarily increased range and prolonged duration of lingual movement accompanied by increased speed parameters, when compared with healthy controls. The findings of the present study contradict theories that suggest that the clinical features of hypokinetic dysarthria, including articulatory imprecision, are the outcome of restrictions in the range of movement of the muscles of the articulators. The observed prolonged duration of lingual movement in PD may plausibly be due to the observed increased range of lingual movement rather than slowness of lingual movement.

Encoding, memory, and transcoding deficits in Childhood Apraxia of Speech

A central question in Childhood Apraxia of Speech (CAS) is whether the core phenotype is limited to transcoding (planning/programming) deficits or if speakers with CAS also have deficits in auditory-perceptual encoding (representational) and/or memory (storage and retrieval of representations) processes. We addressed this and other questions using responses to the Syllable Repetition Task (SRT) [Shriberg, L. D., Lohmeier, H. L., Campbell, T. F., Dollaghan, C. A., Green, J. R., & Moore, C. A. (2009). A nonword repetition task for speakers with misarticulations: The syllable repetition task (SRT). Journal of Speech, Language, and Hearing Research, 52, 1189–1212]. The SRT was administered to 369 individuals in four groups: (a) typical speech–language (119), (b) speech delay–typical language (140), (c) speech delay–language impairment (70), and (d) idiopathic or neurogenetic CAS (40). CAS participants had significantly lower SRT competence, encoding, memory, and transcoding scores than controls. They were 8.3 times more likely than controls to have SRT transcoding scores below 80%. We conclude that speakers with CAS have speech processing deficits in encoding, memory, and transcoding. The SRT currently has moderate diagnostic accuracy to identify transcoding deficits, the signature feature of CAS.

Oral and hand movement speeds are associated with expressive language ability in children with speech sound disorder.

This study tested the hypothesis that children with speech sound disorder have generalized slowed motor speeds. It evaluated associations among oral and hand motor speeds and measures of speech (articulation and phonology) and language (receptive vocabulary, sentence comprehension, sentence imitation), in 11 children with moderate to severe SSD and 11 controls. Syllable durations from a syllable repetition task served as an estimate of maximal oral movement speed. In two imitation tasks, nonwords and clapped rhythms, unstressed vowel durations and quarter-note clap intervals served as estimates of oral and hand movement speed, respectively. Syllable durations were significantly correlated with vowel durations and hand clap intervals. Sentence imitation was correlated with all three timed movement measures. Clustering on syllable repetition durations produced three clusters that also differed in sentence imitation scores. Results are consistent with limited movement speeds across motor systems and SSD subtypes defined by motor speeds as a corollary of expressive language abilities.

Acceleration of syllable repetition in Parkinson's disease is more prominent in the left-side dominant patients

BackgroundIn Parkinson's disease (PD), abnormalities of speech rate have been observed in spontaneous speech, reading tasks and syllable repetition tasks. Impaired temporal speech patterns have been contributed to dysfunctional basal ganglia circuits, but little is known about a possible differential role of right and left basal ganglia concerning speech production, although neurodegeneration in PD typically follows an asymmetrical pattern. The aim of our study was to reveal a possible influence of lateralized basal ganglia dysfunction on speech timing in PD. Patients and methods60 patients with PD (30 with predominant symptoms on the left-side PD_L and 30 with predominant symptoms on the right side PD_R) and 40 healthy controls were tested. Participants had to repeat a single syllable in a self chosen steady pace. Additionally, the participants performed a reading task in order to measure speaking rate related to connected speech. ResultsSyllable repetition showed a significant instability in both PD groups as compared to controls. However, the PD_L group performed in a much higher pace with further significant pace acceleration in the course of the syllable repetition task. This pattern showed a further correlation to axial motor symptoms. No correlations were seen between parameters of syllable repetition and the reading task. ConclusionsLateralization of basal ganglia dysfunction in PD seems to differentially impact the stability of spontaneous syllable repetition pace. Our data suggest a crucial role of the right basal ganglia in the maintenance of isochronous speech rhythms at least in patients with additional axial motor symptoms.

Kinematic analysis of lingual movements during consonant productions in dysarthric speakers with Friedreich's ataxia: A case-by-case analysis

Articulatory kinematics were investigated using electromagnetic articulography (EMA) in four dysarthric speakers with Friedreich's ataxia (FRDA). Specifically, tongue-tip and tongue-back movements were recorded by the AG-200 EMA system during production of the consonants /t/ and /k/ as produced within a sentence utterance and during a rapid syllable repetition task. The results obtained for each of the participants with FRDA were individually compared to those obtained by a control group (n = 10). Results revealed significantly greater movement durations and increased articulatory distances, most predominantly during the approach phase of consonant production. A task difference was observed with lingual kinematics more disturbed during the syllable repetition task than during the sentence utterance. Despite expectations of slowed articulatory movements in FRDA dysarthria, the EMA data indicated that the observed prolongation of consonant phase durations was generally associated with greater articulatory distances, rather than slowed movement execution.

Instability of syllable repetition as a model for impaired motor processing: is Parkinson’s disease a “rhythm disorder”?

Alterations of speech rate and rhythm are well-known features in parkinsonian patients suffering from hypokinetic dysarthria and are thought to be induced by complex dysfunction of planning, preparing and executing of motor speech sequences. Since speech can be subdivided down to the level of single utterances, the aim of our study was to test the hypothesis of a fundamental impairment of vocal pace performance in parkinsonian patients based on a syllable repetition paradigm. Furthermore, the overall integrity of acoustical feedback mechanisms was surveyed by testing the ability to correctly identify pace and steadiness of the presented audio examples. N = 73 patients with Parkinson's disease (PD) and n = 43 age-matched healthy controls were tested. Participants had to repeat the syllable/pa/at least 30 times at a "comfortable" self-chosen steady (isochronous) pace. Percent coefficient of variance (COV) of interval length and the change in interval length with successive utterances were measured for the description of pace stability throughout the performance. Then, participants had to identify irregularities of 30 played-back audio tests. The number of incorrect classification was defined as the error rate (ER). Patients with PD showed significant difficulties in steadily executing a syllable repetition task with a significant elevation of COV and showed a clear tendency to pace acceleration in the course of the performance. However, we found no differences in the correct auditory identification of rhythm irregularities between the PD group and controls. As compared to healthy controls, the PD group features disabilities in performing a steady sequence of utterances, which cannot be explained solely by impaired acoustical feedback mechanisms. The pattern of pace disturbance shows similarities with the finding of speech acceleration and rhythm irregularity in the course of reading or more complex conversational speech and therefore might share the same pathophysiology. Further studies are necessary to reveal the correlations between speech rhythm and motor performance to identify the underlying mechanisms that lead to "dysrhythmia" in PD.

The contribution of mesiofrontal cortex to the preparation and execution of repetitive syllable productions: An fMRI study

Clinical data indicate that the brain network of speech motor control can be subdivided into at least three functional–neuroanatomical subsystems: (i) planning of movement sequences (premotor ventrolateral–frontal cortex and/or anterior insula), (ii) preparedness for/initiation of upcoming verbal utterances (supplementary motor area, SMA), and (iii) on-line innervation of vocal tract muscles, i.e., motor execution (corticobulbar system, basal ganglia, cerebellum). Using an event-related design, this functional magnetic resonance imaging (fMRI) study sought to further delineate the contribution of SMA to pre-articulatory processes of speech production (preceding the innervation of vocal tract muscles) during an acoustically paced syllable repetition task forewarned by a tone signal. Hemodynamic activation across the whole brain and the time courses of the responses in five regions of interest (ROIs) were computed. First, motor preparation was associated with a widespread bilateral activation pattern, encompassing brainstem structures, SMA, insula, premotor ventrolateral–frontal areas, primary sensorimotor cortex (SMC), basal ganglia, and the superior cerebellum. Second, calculation of the time courses of BOLD (“blood oxygenation level-dependent”) signal changes revealed the warning stimulus to elicit synchronous onset of hemodynamic activation in these areas. However, during 4-s intervals of syllable repetitions SMA and cerebellum showed opposite temporal activation patterns in terms of a shorter (SMA) and longer (cerebellum) latency of the entire BOLD response—as compared to SMC, indicating different pacing mechanisms during the initial and the ongoing phase of the task. Nevertheless, the contribution of SMA was not exclusively restricted to the preparation/initiation of verbal responses since the extension of mesiofrontal activation varied with task duration.

A Functional Frontal Cerebral Asymmetry: The Link Between Verbal Articulation Speed and Estradiol in Premenopausal Women

Event Abstract Back to Event A Functional Frontal Cerebral Asymmetry: The Link Between Verbal Articulation Speed and Estradiol in Premenopausal Women D. Mazmanian1 and K Oinonen1* 1 Lakehead University, Department of Psychology, Canada Previous research has suggested functional frontal cerebral asymmetry across the menstrual cycle. Verbal articulation speed appears faster during high hormone phases of the menstrual cycle. The present study examined whether changes in estradiol levels across the menstrual cycle are associated with changes in verbal articulatory speed. Fifty-one free-cycling premenopausal women with regular predictable menstrual cycles completed tests of verbal articulation speed at two different points in their menstrual cycle. Salivary samples were taken twice during both sessions and assayed for estradiol and progesterone. The results support the hypothesis that changes in estradiol are positively associated with changes in verbal articulation speed for simple syllable repetition tasks. These findings could be explained by estradiol-associated: (a) increases in neuronal spine density in the dorsolateral prefrontal cortex (e.g., Tang et al., 2004), (b) increases in 5-HT2A receptor binding in the right frontal lobe (Kugaya et al., 2003), and/or (c) cessation of interhemispheric inhibition whereby areas of the left frontal lobe release their inhibition of the homotopic areas of the right frontal lobe (e.g., Weis et al., 2008). These findings highlight the impact of estradiol on cognition and the need to control for menstrual cycle phase in studies examining certain cognitive abilities in women. Conference: The 20th Annual Rotman Research Institute Conference, The frontal lobes, Toronto, Canada, 22 Mar - 26 Mar, 2010. Presentation Type: Poster Presentation Topic: Cognitive Neuroscience Citation: Mazmanian D and Oinonen K (2010). A Functional Frontal Cerebral Asymmetry: The Link Between Verbal Articulation Speed and Estradiol in Premenopausal Women. Conference Abstract: The 20th Annual Rotman Research Institute Conference, The frontal lobes. doi: 10.3389/conf.fnins.2010.14.00115 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 30 Jun 2010; Published Online: 30 Jun 2010. * Correspondence: K Oinonen, Lakehead University, Department of Psychology, Thunder Bay, Canada, koinonen@lakeheadu.ca Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers D. Mazmanian K Oinonen Google D. Mazmanian K Oinonen Google Scholar D. Mazmanian K Oinonen PubMed D. Mazmanian K Oinonen Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

A Nonword Repetition Task for Speakers With Misarticulations: The Syllable Repetition Task (SRT)

Conceptual and methodological confounds occur when non(sense) word repetition tasks are administered to speakers who do not have the target speech sounds in their phonetic inventories or who habitually misarticulate targeted speech sounds. In this article, the authors (a) describe a nonword repetition task, the Syllable Repetiton Task (SRT), that eliminates this confound and (b) report findings from 3 validity studies. Ninety-five preschool children with speech delay and 63 with typical speech completed an assessment battery that included the Nonword Repetition Task (NRT; C. Dollaghan & T. F. Campbell, 1998) and the SRT. SRT stimuli include only 4 of the earliest occurring consonants and 1 early occurring vowel. Study 1 findings indicated that the SRT eliminated the speech confound in nonword testing with speakers who misarticulate. Study 2 findings indicated that the accuracy of the SRT to identify expressive language impairment was comparable to findings for the NRT. Study 3 findings illustrated the SRT's potential to interrogate speech processing constraints underlying poor nonword repetition accuracy. Results supported both memorial and auditory-perceptual encoding constraints underlying nonword repetition errors in children with speech-language impairment. The SRT appears to be a psychometrically stable and substantively informative nonword repetition task for emerging genetic research and other research with speakers who misarticulate.

Balance and Motor Speech Impairment in Essential Tremor

The pathogenesis of essential tremor (ET) is still under debate. Several lines of evidence indicate that ET is associated with cerebellar dysfunction. The aim of the present study was to find corroborating evidence for this claim by investigating balance and speech impairments in patients with ET. In addition, the effect of deep brain stimulation (DBS) on balance and speech function was studied. A group of 25 ET patients including 18 with postural and/or simple kinetic tremor (ETpt) and seven ET patients with additional clinical signs of cerebellar dysfunction (ETc) was compared to 25 healthy controls. In addition, 12 ET patients with thalamic DBS participated in the study. Balance control was assessed during gait and stance including tandem gait performed on a treadmill as well as static and dynamic posturography. Motor speech control was analyzed through syllable repetition tasks. Signs of balance impairment were found in early stages and advanced stages of ET. During locomotion, ET patients exhibited an increased number of missteps and shortened stride length with tandem gait. ETc patients and, to a lesser extent, ETpt patients had increased postural instability in dynamic posturography conditions that are sensitive to vestibular or vestibulocerebellar dysfunction. ETc but not ETpt patients exhibited significantly increased syllable durations. DBS had no discernable effect on speech performance or balance control. We conclude that the deficits in balance as well as the subclinical signs of dysarthria in a subset of patients confirm and extend previous findings that ET is associated with an impairment of the cerebellum.

Tipo de estímulo e memória de trabalho fonológica

OBJETIVO: investigar a influência do modo de apresentação do estímulo lingüístico sobre a memória de trabalho fonológica. MÉTODOS: avaliaram-se 27 escolares (59,25% meninas) entre sete anos, sete meses e oito anos, sete meses, da 2ª série do Ensino Fundamental de Escola Pública, sem histórico de retenção, ou queixas de déficits neurológicos, cognitivos ou auditivos. Passaram na Avaliação Simplificada do Processamento Auditivo e foram submetidos à tarefa de repetição de sílabas ou pseudopalavras. Os estímulos foram gravados e apresentados como: I) fluentes: lista de pseudopalavras, com intervalos de dez segundos entre uma e outra, apresentada a 13 escolares, e II) silabados, lista apresentada a 14 escolares, com intervalo de um segundo entre cada sílaba e dez segundos entre cada seqüência. As repetições foram transcritas, os erros assinalados e comparados segundo o sexo e o modo de apresentação do estímulo. RESULTADOS: na análise geral do desempenho notou-se diferença, com melhor desempenho na apresentação da lista II e, a partir dos estímulos de cinco sílabas, maiores porcentagens de acerto na apresentação da lista I, quando comparada à II. A comparação entre os sexos mostrou diferença significante para estímulos de cinco sílabas na análise geral e da lista II, com melhores resultados dos meninos. CONCLUSÃO: não houve diferença de desempenho até a extensão de quatro sílabas. A apresentação na forma fluente facilitou o desempenho da memória fonológica de trabalho dos escolares do sexo masculino e feminino quando os estímulos apresentados foram mais extensos.

Articulatory Variability in Cluttering

In order to investigate the articulatory processes of the hasty and mumbled speech in cluttering, the kinematic variability was analysed by means of electromagnetic midsagittal articulography. In contrast to persons with stuttering, those with cluttering improve their intelligibility by concentrating on their speech task. Variability has always been an important criterion in comparable studies of stuttering and is discussed in terms of the stability of the speech motor system. The aim of the current study was to analyse the spatial and temporal variability in the speech of three persons with cluttering (PWC) and three control speakers. All participants were native speakers of German. The speech material consisted of repetitive CV syllables and loan words such as ‘emotionalisieren’, because PWC have the severest problems with long words with a complex syllable structure. The results showed a significantly higher coefficient of variation for PWC in loan word production, both in the temporal and in the spatial domain, whereas the means of displacements and durations did not differ between groups. These findings were discussed in terms of the effects of the linguistic complexity, since for the syllable repetition task, no significant differences between PWC and controls were found.

Physiologic and behavioral classification of delayed speech: Syllable repetition tasks

As part of a large-scale study that aims to create a data-driven model of speech delay of unknown origin (SD) in preschool children, this investigation analyzed two- and three-syllable nonword repetitions by 50 3- to 5-year-old children, half of whom are typically developing (TD). The syllable repetition task was composed of four different words, bama, bada, bamana, and manaba, selected both for articulatory simplicity and to maximize displacement of the external articulators for kinematic analyses. While children in the TD group were significantly more accurate in both two- and three-syllable repetitions than children in the SD group, neither group was able to repeat three-syllable nonwords with particular acumen. Children in the TD group were 55% accurate, while children in the SD group were only 22% accurate. Measures of repetition accuracy, acoustics, nasalence, external articulatory kinematics, and respiration contribute to a hierarchical agglomerative clustering model that generates hypotheses about potential subclinical categories within the SD and TD groups.

Verb generation in children and adolescents with acute cerebellar lesions

The aim of the present study was to examine verb generation in a larger group of children and adolescents with acute focal lesions of the cerebellum. Nine children and adolescents with cerebellar tumours participated. Subjects were tested a few days after tumour surgery. For comparison, a subgroup was tested also 1 or 2 days before surgery. None of the children had received radiation or chemotherapy at or before the time of testing. Eleven age- and education-matched control subjects participated. Subjects had to generate verbs to blocked presentations of photographs of objects. As control condition, the objects had to be named. Furthermore, dysarthria was quantified by means of a sentence production and syllable repetition task. Detailed analysis of individual 3D-MR images revealed that lesions affected cerebellar hemispheres in all children and adolescents. The right cerebellar hemisphere was affected in four and the left hemisphere in five subjects. In the present study, naming and verb generation accuracy were preserved in the majority of subjects with cerebellar lesions. No significant signs of learning deficits were observed, as reduction of reaction times over blocks was not different compared to controls. There was a trend of children and adolescents with right-hemispheric lesions to perform worse compared to controls. In this group, however, significant signs of dysarthria were present. In sum, no significant signs of disordered verb generation were observed in children and adolescents with acute cerebellar lesions. Findings suggest that the role of the cerebellum in verb generation may be less pronounced than previously suggested. Findings need to be confirmed in a larger group of subjects with acute focal lesions.

M-Mode Color Doppler Ultrasonic Imaging of Vertical Tongue Movement During Articulatory Movement

To observe and estimate the movement of the tongue, ultrasonic investigation is the most harmless real-time monitoring procedure for analyzing articulatory movements. Color Doppler ultrasonic imaging is special in that it can only sample a moving target, and it can indicate the velocity and direction of the target by color and brightness in real time. This study assessed and demonstrated the validity of M-mode color Doppler ultrasonic imaging to observe the movements of the tongue during syllable repetition tasks performed by normal subjects and dysarthric patients, those affected by amyotrophic lateral sclerosis, cerebellar ataxia, Parkinsonism, and polymyopathy. When the transducer was set below the jaw, upward movement was indicated by a blue signal and downward movement was indicated by a red one on the screen of the ultrasound machine. We also measured the velocity of the tongue by contrast scale classified by 15 degrees. Thus, we could observe vertical tongue movement by a color-coded pattern after quantitative analysis. The Doppler signal patterns of normal subjects were verified by simultaneous video x-ray fluorography recordings. The findings for dysarthric patients corresponded well with previously reported features analyzed by other methods. Therefore, color Doppler ultrasonic imaging of the tongue is a useful procedure to researchers for clinical speech and voice studies.

Articulatory variability of clutterers

In order to investigate the articulatory processes of the hasty and mumbled speech of clutterers, the kinematic variability was analysed by means of electromagnetic midsagittal articulography (EMMA). In contrast to stutterers, clutterers improve their intelligibility by concentrating on their speech task. Variability is an important criterion in comparable studies of stuttering and is discussed in terms of the stability of the speech motor system. The aim of the current study was to analyse the spatial and temporal variability in the speech of three clutterers and three control speakers. All speakers were native speakers of German. The speech material consisted of repetitive CV-syllables and foreign words, because clutterers have the most severe problems with long words which have a complex syllable structure. The results showed a higher quotient of variation for clutterers in the foreign word production. For the syllable repetition task, no significant differences between clutterers and controls were found. The extremely large and variable displacements were interpreted as a strategy that helps clutterers to improve the intelligibility of their speech.

Incidence of dysarthria in children with cerebellar tumors: A prospective study

The present study investigated dysarthric symptoms in children with cerebellar tumors. Ten children with cerebellar tumors and 10 orthopedic control children were tested prior and one week after surgery. Clinical dysarthric symptoms were quantified in spontaneous speech. Syllable durations were analyzed in syllable repetition and sentence production tasks. Localization of the cerebellar lesions were defined after manual transfer from individual 2D-MR images onto 3D images of a spatially normalized healthy brain. Cerebellar children showed few and mild clinical signs of dysarthria. No difference was present in the sentence production task compared to controls. In five cerebellar children, syllables were prolonged in the syllable repetition task after surgery. Syllable duration normalized in an additional four-week session in all but one case. The MR-analysis showed that superior paravermal cerebellar areas likely involved in dysarthria in adults (paravermal lobules HVI, Crus I) were not significantly affected. In children, speech impairments appear to be rare after cerebellar surgery because tumors most commonly affect posterior–inferior and medial parts of the cerebellum while critical cerebellar regions are likely spared. The results suggest a similar localization of speech functions in the cerebellum in children and adults.