Normal intracortical excitability in developmental stuttering.

Persistent developmental stuttering (PDS) shares clinical features with task-specific dystonias. In these dystonias, intracortical inhibition is abnormally weak. We therefore sought to determine intracortical inhibition and intracortical facilitation in PDS. In 18 subjects with PDS since childhood (mean age, 39.4 [SD 13.0] years) and 18 speech-fluent controls (43.6 [14.3] years), we investigated resting and active motor thresholds as well as intracortical inhibition and facilitation of the optimal representation of the abductor digiti minimi of the dominant hand using transcranial magnetic stimulation. In PDS, the resting and active motor thresholds were increased, whereas intracortical inhibition and facilitation were normal. Normal intracortical excitability makes a pathophysiological analogy between focal dystonia and PDS less likely. The enhanced motor threshold suggests reduced motor cortical neuronal membrane excitability in PDS.     

Effectiveness of the Lidcombe Program for early stuttering in Australian community clinics

Abstract

This study explored the effectiveness of the Lidcombe Program for early stuttering in community clinics. Participants were 31 speech-language pathologists (SLPs) using the Lidcombe Program in clinics across Australia, and 57 of their young stuttering clients. Percentage of syllables stuttered (%SS) was collected 9 months after beginning treatment along with information about variables likely to influence outcomes. The mean %SS for the 57 children 9 months after starting treatment was 1.7. The most significant predictor of outcome was Lidcombe Program Trainers Consortium (LPTC) training. The children of trained SLPs (n = 19), compared to the children of untrained SLPs, took 76% more sessions to complete stage 1, but achieved 54% lower %SS scores, 9 months after starting treatment. Results suggest that outcomes for the Lidcombe Program in the general community may be comparable to those obtained in clinical trials when SLPs receive formal training and support.     

Changes in the pattern of stuttering over development for children who recover or persist

Three schemes for assessing stuttering were compared. They differed with respect to whether they included whole-word repetitions as characteristics more typical of stuttering. Persistent and recovered groups of children were examined to see whether: (1) one of the schemes differentiated the groups better than others; (2) more and less typical of stuttering characteristics changed over ages in different ways for the groups; and (3) the changes over ages of more and less typical of stuttering classes depended on word type. Twenty-six children who stuttered were classified as persistent or recovered and recorded at three ages between 8–12+ years. Stuttering characteristics were obtained according to the three schemes. The results show: (1) All schemes distinguished persistent, from recovered, children. (2) The proportion of less typical of stuttering characteristics increased and more typical of stuttering characteristics decreased over age for recovered children for all three schemes (there was no change for persistent children). (3) The increased proportion of less typical of stuttering characteristics for the recovered children across age was more apparent for one-syllable content words than one-syllable function words.     

发展性口吃者汉字认知加工基本能力的考察

目的考察发展性口吃者汉字形、音、义加工的成绩,探讨其汉语认知的基本能力。方法应用手动反应时实验范式,检测了17名发展性口吃者和17名流利言语者完成汉字形、音、义3种判断任务的反应时和错误率。结果发展性口吃者与流利言语者完成汉字形、音、义判断任务的反应时以及字形和字义判断的错误率之间均无显著性差异（P〉0.05）,仅字音判断错误率的差异接近显著（P=0.053）。结论发展性口吃者仅在字音正确提取或编码方面的能力有降低的倾向,部分支持隐蔽修复假说中口吃与语音编码缺陷有关的观点。     

Stuttering on function words in bilingual children who stutter: A preliminary study

Evidence suggests young monolingual children who stutter (CWS) are more disfluent on function than content words, particularly when produced in the initial utterance position. The purpose of the present preliminary study was to investigate whether young bilingual CWS present with this same pattern. The narrative and conversational samples of four bilingual Spanish- and English-speaking CWS were analysed. All four bilingual participants produced significantly more stuttering on function words compared to content words, irrespective of their position in the utterance, in their Spanish narrative and conversational speech samples. Three of the four participants also demonstrated more stuttering on function compared to content words in their narrative speech samples in English, but only one participant produced more stuttering on function than content words in her English conversational sample. These preliminary findings are discussed relative to linguistic planning and language proficiency and their potential contribution to stuttered speech.     

Early-stage chunking of finger tapping sequences by persons who stutter and fluent speakers

This research note explored the hypothesis that chunking differences underlie the slow finger-tap sequencing performance reported in the literature for persons who stutter (PWS) relative to fluent speakers (PNS). Early-stage chunking was defined as an immediate and spontaneous tendency to organize a long sequence into pauses, for motor planning, and chunks of fluent motor performance. A previously published study in which 12 PWS and 12 matched PNS practised a 10-item finger tapping sequence 30 times was examined. Both groups significantly decreased the duration of between-chunk intervals (BCIs) and within-chunk intervals (WCIs) over practice. PNS had significantly shorter WCIs relative to PWS, but minimal differences between groups were found for the number of, or duration of, BCI. Results imply that sequencing differences found between PNS and PWS may be due to differences in automatizing movements within chunks or retrieving chunks from memory rather than chunking per se.     

Neuropsychological Profile of Stuttering Children

The purpose of this study was to analyze the cognitive profile of stuttering children. A sample of 290 children was obtained from an elementary school in Bogota (Colombia) (149 boys, 141 girls). Three right-handed boys were classified as stutterers. In general, performance in stuttering children was similar to the performance in the total sample. Statistically significant differences in two test scores were observed, with a higher performance in the stuttering group: Finger Tapping Test with the left hand and Quantitative Concepts from the Woodcock Psychoeducational Battery. These results do not support the existence of any cognitive deficit in stuttering children when using standard neuropsychological testing procedures. However, in two of three stuttering children, some developmental abnormalities were mentionded by their parents (hyperactivity associated with inattention in one child and difficulties in learning to read in the other child). It is proposed that these developmental abnormalities might be the result of the emotional and communication difficulties generally associated with stuttering. These results, on the other hand, support a bihemispheric control of fine movements, as has been frequently mentioned in stuttering research.     

Segmental transition of the first syllables of words in Japanese children who stutter: Comparison between word and sentence production

Matsumoto-Shimamori, Ito, Fukuda, & Fukuda (2011) proposed the hypothesis that in Japanese, the transition from the core vowels (i.e. syllable nucleus) of the first syllables of words to the following segments affected the occurrence of stuttering. Moreover, in this transition position, an inter-syllabic transition precipitated more stuttering than an intra-syllabic one (Shimamori & Ito, 2007, 2008). However, these studies have only used word production tasks. The purpose of this study was to investigate whether the same results could be obtained in sentence production tasks. Participants were 28 Japanese school-age children who stutter, ranging in age from 7;3 to 12;7. The frequency of stuttering on words with an inter-syllabic transition was significantly higher than on those having an intra-syllabic transition, not only in isolated words but in the first words of sentences. These results suggested that Matsumoto et al.’s hypothesis could be applicable to the results of sentence production tasks.