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.     

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.     

Hemispheric specialization for speech perception in language deficient kindergarten children

Twenty right-handed kindergarten children with superior language skills and twenty with deficient language skills (as defined by performance on an elicited sentence repetition task) were tested (1) for hemispheric specialization for speech perception with a dichotic CV syllable task and (2) for relative manual proficiency by means of a battery of hand tasks. Reading readiness and aspects of other cognitive abilities were also assessed. The superior children evidenced a mean right-ear advantage of 14.5%, which is consistent with normal values reported by other investigators using the same stimuli. The language deficient group evidenced essentially no mean ear advantage (0.5) with half of these subjects exhibiting left-ear superiority. The findings suggest relationships among cerébral dominance, language proficiency (including reading readiness), and general cognitive functioning.     

Imitation of body postures and hand movements in children with specific language impairment

Within the domain-general theory of language impairment, this study examined body posture and hand movement imitation in children with specific language impairment (SLI) and in their age-matched peers. Participants included 40 children with SLI (5 years 3 months to 6 years 10 months of age) and 40 children with typical language development (5 years 3 months to 6 years 7 months of age). Five tests were used to examine imitation and its underlying cognitive and motor skills such as kinesthesia, working memory, and gross motor coordination. It was hypothesized that children with SLI show a weakness in imitation of body postures and that this deficit is not equally influenced by the underlying cognitive and motor skills. There was a group effect in each cognitive and motor task, but only gross motor coordination proved to be a strong predictor of imitation in children with SLI. In contrast, hand movement imitation was strongly predicted by performance in the Kinesthesia task in typically developing children. Thus, the findings show not only that children with SLI performed more poorly on the imitation tasks than their typically developing peers but also that the groups’ performances showed qualitative differences. The results of the current study provide additional support to the view that the weaknesses in children with SLI are not limited to the verbal domain.     

Sentence repetition is a measure of children's language skills rather than working memory limitations

Sentence repetition tasks are widely used in the diagnosis and assessment of children with language difficulties. This paper seeks to clarify the nature of sentence repetition tasks and their relationship to other language skills. We present the results from a 2‐year longitudinal study of 216 children. Children were assessed on measures of sentence repetition, vocabulary knowledge and grammatical skills three times at approximately yearly intervals starting at age 4. Sentence repetition was not a unique longitudinal predictor of the growth of language skills. A unidimensional language latent factor (defined by sentence repetition, vocabulary knowledge and grammatical skills) provided an excellent fit to the data, and language abilities showed a high degree of longitudinal stability. Sentence repetition is best seen as a reflection of an underlying language ability factor rather than as a measure of a separate construct with a specific role in language processing. Sentence repetition appears to be a valuable tool for language assessment because it draws upon a wide range of language processing skills.     

Task-related factors in oral motor control: speech and oral diadochokinesis in dysarthria and apraxia of speech

This study was focused on the potential influence of task-related factors on oral motor performance in patients with speech disorders. Sentence production was compared with a nonspeech oral motor task, i.e., oral diadochokinesis. Perceptual and acoustic measures of speech impairment were used as dependent variables. Between-task comparisons were made for subsamples of a population of 140 patients with different motor speech syndromes, including apraxia of speech and cerebellar dysarthria. In a further analysis subgroups were matched for speaking rate. Overall, dysdiadochokinesis was correlated with the degree of speech impairment, but there was a strong interaction between task type and motor speech syndrome. In particular, cerebellar pathology affected DDK to a relatively greater extent than sentence production, while apraxic pathology spared the ability of repeating syllables at maximum speed.     

A Comparison of Phonological Awareness Skills in Early French Immersion and English Children

This 2-year study examined the effects of early second language exposure on phonological awareness skills. Syllable, onset-rime and phoneme awareness skills of 72 anglophone children attending English or French immersion programs in primary and grade 1 were investigated. Three-way mixed ANOVAS revealed the following effects and interactions. In terms of grade effect, grade 1 students performed significantly better than primary students on phoneme and onset-rime tasks. A stimulus language effect was observed for the three levels of phonological awareness. All children performed better on English tasks than on French ones. Interaction effects of stimulus language by program were revealed for phoneme as well as syllable tasks. Posthoc analyses revealed that French students performed better on English phoneme and syllable tasks than on French, while English students performed better than French immersion students on French syllable tasks. Correlational analyses revealed significant relationships between reading and phoneme and onset-rime phonological awareness tasks regardless of program of instruction (English, French immersion) or language of reading test (English, French). Syllable awareness was only significantly correlated with the French non-word reading task for the French immersion students.     

Language and motor abilities of preschool children who stutter: Evidence from behavioral and kinematic indices of nonword repetition performance

Stuttering is a disorder of speech production that typically arises in the preschool years, and many accounts of its onset and development implicate language and motor processes as critical underlying factors. There have, however, been very few studies of speech motor control processes in preschool children who stutter. Hearing novel nonwords and reproducing them engages multiple neural networks, including those involved in phonological analysis and storage and speech motor programming and execution. We used this task to explore speech motor and language abilities of 31 children aged 4–5 years who were diagnosed as stuttering. We also used sensitive and specific standardized tests of speech and language abilities to determine which of the children who stutter had concomitant language and/or phonological disorders. Approximately half of our sample of stuttering children had language and/or phonological disorders. As previous investigations would suggest, the stuttering children with concomitant language or speech sound disorders produced significantly more errors on the nonword repetition task compared to typically developing children. In contrast, the children who were diagnosed as stuttering, but who had normal speech sound and language abilities, performed the nonword repetition task with equal accuracy compared to their normally fluent peers. Analyses of interarticulator motions during accurate and fluent productions of the nonwords revealed that the children who stutter (without concomitant disorders) showed higher variability in oral motor coordination indices. These results provide new evidence that preschool children diagnosed as stuttering lag their typically developing peers in maturation of speech motor control processes.Educational objectives: The reader will be able to: (a) discuss why performance on nonword repetition tasks has been investigated in children who stutter; (b) discuss why children who stutter in the current study had a higher incidence of concomitant language deficits compared to several other studies; (c) describe how performance differed on a nonword repetition test between children who stutter who do and do not have concomitant speech or language deficits; (d) make a general statement about speech motor control for nonword production in children who stutter compared to controls.     

Neural correlates of phonological processing in speech sound disorder: a functional magnetic resonance imaging study

Speech sound disorders (SSD) are the largest group of communication disorders observed in children. One explanation for these disorders is that children with SSD fail to form stable phonological representations when acquiring the speech sound system of their language due to poor phonological memory (PM). The goal of this study was to examine PM in individuals with histories of SSD employing functional MR imaging (fMRI). Participants were six right-handed adolescents with a history of early childhood SSD and seven right-handed matched controls with no history of speech and language disorders. We performed an fMRI study using an overt non-word repetition (NWR). Right lateralized hypoactivation in the inferior frontal gyrus and middle temporal gyrus was observed. The former suggests a deficit in the phonological processing loop supporting PM, while the later may indicate a deficit in speech perception. Both are cognitive processes involved in speech production. Bilateral hyperactivation observed in the pre and supplementary motor cortex, inferior parietal, supramarginal gyrus and cerebellum raised the possibility of compensatory increases in cognitive effort or reliance on the other components of the articulatory rehearsal network and phonologic store. These findings may be interpreted to support the hypothesis that individuals with SSD may have a deficit in PM and to suggest the involvement of compensatory mechanisms to counteract dysfunction of the normal network.     

Differential vowel duration associated with children's word-final fricative deletion.

This study assessed whether 3 children, 5 to 6 years old, who deleted word-final fricatives preserve the voicing contrast for those fricatives by producing dif ferential duration of the preceding vowel. The children's CV syllable productions were compared to their CV(C) syllable productions in which the final consonant was intended but actually deleted. Analysis indicated that all 3 children exhibited significantly longer vowel duration, in CV syllables than in CV(C) syllables. This differential duration of the preceding vowel was shown in both isolation and carrier phrase conditions. Of the 3 children 2 preserved the voicing contrast by showing significantly longer vowels preceding voiced consonants as compared to voiceless consonants. One child did this in both isolation and carrier phrase conditions and the other child did this in isolation only. All 3 children manipulated vowel duration to signify the linguis tic contrast, therefore these findings support a linguistic perspective of speech development which focuses on the acquisition and knowledge of the linguistic rules of the language. In addition, the large amount of variability in vowel duration for CV and CV(C) syllables and the marked variability in performance across children support a biological view of a developing vocal tract undergoing structural and physiological changes.     

AN ALTERNATING TREATMENTS COMPARISON OF ORAL AND TOTAL COMMUNICATION TRAINING WITH MINIMALLY VERBAL RETARDED CHILDREN

This study was a comparison of the effects of oral speech with total communication (speech plus sign language) training on the ability of mentally retarded children to repeat 4-word sentences. Three children were chosen who used single words to communicate but who did not combine words into complete sentences. Three sentence pairs were trained, with each pair having one sentence trained using oral methods and an equivalent one trained using the total communication approach. Both training procedures involved chaining sentence parts, reinforcement, and prompting. Oral methods involved presenting vocal stimuli and requiring vocal responses whereas total communication methods involved presenting vocal and signed stimuli and requiring vocal and signed responses. For the initial sentence pair with each child, an alternating treatments design was used to determine the relative efficacy of the two language training approaches. This was repeated with a second and third sentence pair using a multiprobe technique within a multiple baseline design. Results pointed to the superiority of the total communication approach in facilitating sentence repetition. Possible explanations of these results are offered and the utility of the alternating treatments experimental design is discussed.     

Progressive dysfluency associated with right hemisphere disease

A late onset progressive dysfluency following a right hemisphere stroke occurred in a 62-year-old male. Dysfluency was characterized by pronounced word and phrase reiterations, and sound and syllable reiterations to a lesser degree. Spontaneous speech was significantly more dysfluent than oral reading and repetition. Recitation and singing were minimally dysfluent. Reiterations were accompanied by reduced vocal loudness and increased rate of speech. Reiterations occurred in initial, medial, and final sentence position. Secondary symptoms such as facial grimacing were absent. In contrast to acquired cortical stuttering which is characterized by a preponderance of sound and syllable sentence initial repetitions, dysfluency was more closely characteristic of palilalia. The dysfluency occurred as a symptom of a diffuse nonspecific subcortical projection system defect related to massive infarction in the right middle cerebral artery distribution with associated atrophy.     

Syntactic,semantic, and rhythmic influences on children's and adults' motor programming of speech

The influence of linguistic and paralinguistic structure on speech motor programming was investigated for 5-year-olds, 8-year-olds, and adults. Subjects repeated verbal stimuli, each at maximum rate on numerous consecutive trials. It was hypothesized that structure in an utterance would allow a speaker to organize its motor program more efficiently than would be possible for an otherwise identical utterance that lacked such structure, although the types of structure employed might change with age. Differences in the efficiency of motor program organization were expected to be evidenced in the syllable duration and the relative variability of the syllable duration of subjects' repetitions. At all ages, repetition durations were shorter for stimuli with a sentencelike rhythm than for unstructured stimuli. Stimuli that were syntactically structured and contained a sentencelike rhythm were spoken with shorter durations than nonsyntactic stimuli with sentential rhythm but only by 8-year-olds and adults.     

Syllabic complexity and syntagmatic rules for syllable production-a comment on aspects of the syntax of behaviour by D. G. Mackay

Using a metric of syllabic complexity derived from a syntagmatic theory of syllabic production, in which syllabic recoding expands a syllable into an optional initial consonant group and an obligatory vowel group, MacKay (1974) examined the relationship between the complexity of syllables and their durations in a task of rapid repetition. He concluded from spectrographic measurements of the test syllables that the complexity metric was a good predictor of the syllable durations, and hence syllable repetition rates. The present report demonstrates that comparable, if not better, predictions are made by a simpler theory based on the recoding of syllable structures as series of CV combinations, with appropriate reductions of C or V segments.     

Neural processing of acoustic duration and phonological German vowel length: Time courses of evoked fields in response to speech and nonspeech signals

Recent experiments showed that the perception of vowel length by German listeners exhibits the characteristics of categorical perception. The present study sought to find the neural activity reflecting categorical vowel length and the short-long boundary by examining the processing of non-contrastive durations and categorical length using MEG. Using disyllabic words with varying /a/-durations and temporally-matched nonspeech stimuli, we found that each syllable elicited an M50/M100-complex. The M50-amplitude to the second syllable varied along the durational continuum, possibly reflecting the mapping of duration onto a rhythm representation. Categorical length was reflected by an additional response elicited when vowel duration exceeded the short-long boundary. This was interpreted to reflect the integration of an additional timing unit for long in contrast to short vowels. Unlike to speech, responses to short nonspeech durations lacked a M100 to the first and M50 to the second syllable, indicating different integration windows for speech and nonspeech signals.     

Differential diagnosis between apraxia and dysarthria based on acoustic analysis

Acoustic analysis provides objective quantitative measures of speech that enable a comprehensive and accurate understanding of motor disorders and complement the traditional measures. This paper aims to distinguish between normal and pathological speech, more specifically between apraxia of speech and spastic dysarthria in native Spanish speaking patients using acoustic parameters. Participants (4 aphasic with apraxia of speech, 4 with spastic dysarthria, and 15 without speech disorders) performed three different tasks: repeating the syllable sequence [pa-ta-ka], repeating the isolated syllable [pa] and repeating the vowel sequence [i-u]. The results showed that the normative values of motor control, in general, coincide with those obtained in previous research on native English speakers. They also show that damage to motor control processes results in a decrease in the rate of alternating and sequential movements and an increase in the inter-syllabic time for both types of movements. A subset of the acoustic parameters analyzed, those that measure motor planning processes, enable differentiation between normal population and apraxic and dysarthric patients, and between the latter. The differences between the pathological groups support the distinction between motor planning and motor programming as described by van der Merwe's model of sensorimotor processing (1997).     

Pantomime, praxis, and aphasia.

The production and comprehension of pantomimed movements by asphasic subjects were studied with respect to their relationship to the aphasic deficit on one hand and apraxia on the other. At issue was whether impaired use of pantomime is a manifestation of reduced symbolic capacity or purely a manifestation of an apraxic impairment of purposeful movement or both. Tests of pantomime included a Pantomime Recognition Test, a nonverbal Transitive Pantomime Production Test, and an Intransitive Pantomime Production Test (to oral command). Imitation of Nonmeaningful Movements served as a measure of apraxia, uncontaminated by symbolic or linguistic factors. Imitation of Meaningful Movements taken from the pantomime tasks was also tested. Independent measures of auditory comprehension, picture naming, and reading comprehension were used as indices of language impairment. Intellectual function was measured by the Performance scale of the WAIS. Thirty aphasic subjects were examined. Twenty healthy age-matched normals served to establish scoring standards for the pantomime tests. Multiple regression analysis revealed significant, independent contributions from both auditory comprehension and imitation of Nonmeaningful Movements to all of the tests of pantomime production and pantomime recognition. All measures of pantomime production and pantomime recognition were strongly intercorrelated. While the three language measures were strongly correlated with each other, auditory comprehension was the only one of them that was significantly and consistently related to the pantomime tests. None was related to the imitation of nonmeaningful movement. The results are taken as indicating (1) that pantomime production and imitation share common factors with both praxis and auditory comprehension; (2) apraxia entails impairment of both production and interpretation of purposeful movements. Possible theoretical accounts for these results are offered.     

Effects of stimulus response compatibility on covert imitation of vowels

When we observe someone else speaking, we tend to automatically activate the corresponding speech motor patterns. When listening, we therefore covertly imitate the observed speech. Simulation theories of speech perception propose that covert imitation of speech motor patterns supports speech perception. Covert imitation of speech has been studied with interference paradigms, including the stimulus–response compatibility paradigm (SRC). The SRC paradigm measures covert imitation by comparing articulation of a prompt following exposure to a distracter. Responses tend to be faster for congruent than for incongruent distracters; thus, showing evidence of covert imitation. Simulation accounts propose a key role for covert imitation in speech perception. However, covert imitation has thus far only been demonstrated for a select class of speech sounds, namely consonants, and it is unclear whether covert imitation extends to vowels. We aimed to demonstrate that covert imitation effects as measured with the SRC paradigm extend to vowels, in two experiments. We examined whether covert imitation occurs for vowels in a consonant–vowel–consonant context in visual, audio, and audiovisual modalities. We presented the prompt at four time points to examine how covert imitation varied over the distracter’s duration. The results of both experiments clearly demonstrated covert imitation effects for vowels, thus supporting simulation theories of speech perception. Covert imitation was not affected by stimulus modality and was maximal for later time points.

     

Individual differences in language development: relationship with motor skill at 21 months

Language development has long been associated with motor development, particularly manual gesture. We examined a variety of motor abilities – manual gesture including symbolic, meaningless and sequential memory, oral motor control, gross and fine motor control – in 129 children aged 21 months. Language abilities were assessed and cognitive and socio‐economic measures controlled for. Oral motor control was strongly associated with language production (vocabulary and sentence complexity), with some contribution from symbolic abilities. Language comprehension, however, was associated with cognitive and socio‐economic measures. We conclude that symbolic, working memory, and mirror neuron accounts of language–motor control links are limited, but that a common neural and motor substrate for nonverbal and verbal oral movements may drive the motor–language association.     

Dyslexia: the articulatory hypothesis revisited

Articulatory disorders have been associated with developmental phonological dyslexia in the literature. However, very few information is available about the articulatory movements involved in speech production in dyslexic children. This study uses aerodynamic/acoustic data to explore how dyslexic children produce bilabial stops in French (/b, p/) within a sentence where they occurred in two positions and in three vowel environments. Average durations of articulatory closure and release were calculated in 10 phonological dyslexic children and two groups of age-matched and reading age-matched controls. Moreover, deviation from a standard pronunciation of the same material was evaluated separately by blind examiners. Our results reveal differences in the timing of the articulatory movements between dyslexics and normal controls, as well as more deviations from the target consonant for the dyslexics than for the controls. These observations are consistent with recent findings pointing to a general deficit in fine motor control in dyslexia.