The effect of fast speech rate on stuttering frequency during delayed auditory feedback

Delayed auditory feedback (DAF) has been documented to improve fluency in those who stutter. The increased fluency has been attributed to the slowed speech rate induced by DAF, but recent experiments have suggested that increasing the speech rate may also decrease stuttering under DAF. This investigation described the effect of combining a fast speech rate and DAF on the fluency of four people who stutter. Fluency of the two mildly dysfluent subjects was the same for both no DAF and DAF conditions at normal and at fast oral reading rates. In contrast, the two severely dysfluent subjects improved in fluency from the no DAF to the DAF conditions. They were found to be dysfluent at both normal and fast oral reading rates without DAF. The results of the study point to the need for further research on the relationship between speech rate and stuttering frequency under conditions of DAF and no DAF. EDUCATIONAL OBJECTIVES: Readers will learn about and be able to describe how the frequency of stuttering is affected by: (1) speech rates; (2) DAF; and (3) how stuttering severity influences such effects.     

Auditory‐motor adaptation is reduced in adults who stutter but not in children who stutter

Previous studies have shown that adults who stutter produce smaller corrective motor responses to compensate for unexpected auditory perturbations in comparison to adults who do not stutter, suggesting that stuttering may be associated with deficits in integration of auditory feedback for online speech monitoring. In this study, we examined whether stuttering is also associated with deficiencies in integrating and using discrepancies between expected and received auditory feedback to adaptively update motor programs for accurate speech production. Using a sensorimotor adaptation paradigm, we measured adaptive speech responses to auditory formant frequency perturbations in adults and children who stutter and their matched nonstuttering controls. We found that the magnitude of the speech adaptive response for children who stutter did not differ from that of fluent children. However, the adaptation magnitude of adults who stutter in response to auditory perturbation was significantly smaller than the adaptation magnitude of adults who do not stutter. Together these results indicate that stuttering is associated with deficits in integrating discrepancies between predicted and received auditory feedback to calibrate the speech production system in adults but not children. This auditory‐motor integration deficit thus appears to be a compensatory effect that develops over years of stuttering.     

视觉形状知觉在近似数量系统和计算流畅性关系中的作用

已有大量研究揭示了近似数量系统与计算流畅性的相关关系, 但缺少对二者关系原因的系统检验与论证。视觉形状知觉假设有别于传统的数量领域特异性解释, 认为对形状的快速知觉是近似数量系统与计算流畅性的共同认知机制, 即视觉形状的快速知觉能力可以解释二者之间的相关关系。近似数量系统和计算流畅性在加工过程中依赖对形状的快速知觉, 二者在加工过程中都涉及了复杂视觉刺激的快速处理。视觉形状知觉假设得到了一系列研究结果的支持, 但局限在视觉形状知觉与二者关系的探讨上, 视觉形状知觉在二者关系中作用的加工机制仍不清楚。未来研究需要结合多种研究方法和技术, 多角度深入探讨视觉形状知觉在二者关系中作用的认知与脑机制, 并将研究结果应用于数学课堂教学和计算困难的干预中。     

A positron emission tomography study of short- and long-term treatment effects on functional brain activation in adults who stutter

Previous studies have shown that fluency-inducing techniques, such as choral speech, result in changes in neural activation as measured by functional neuroimaging. In the present study, positron emission tomography was used to investigate the effects of intensive behavioural treatment, followed by a 1-year maintenance program, on the pattern of cortical and subcortical activation in stuttering adults during silent and oral reading of single words. The results indicate changes in activation lateralisation, as well as a general reduction in overactivation, especially in the motor cortex, following treatment. The results are discussed in light of previous functional imaging studies with stuttering adults.

Educational objectives: The reader will learn about and be able to describe the: (1) use of functional neuroimaging PET in the study of stuttering; (2) differences in neural activation between stuttering and non-stuttering adults; and (3) effects of behavioural fluency treatment on cortical and subcortical activations in stuttering speakers.     

The speech naturalness of people who stutter speaking under delayed auditory feedback as perceived by different groups of listeners

This study investigated listeners' perception of the speech naturalness of people who stutter (PWS) speaking under delayed auditory feedback (DAF) with particular attention for possible listener differences. Three panels of judges consisting of 14 stuttering individuals, 14 speech language pathologists, and 14 naive listeners rated the naturalness of speech samples of stuttering and non-stuttering individuals using a 9-point interval scale. Results clearly indicate that these three groups evaluate naturalness differently. Naive listeners appear to be more severe in their judgements than speech language pathologists and stuttering listeners, and speech language pathologists are apparently more severe than PWS. The three listener groups showed similar trends with respect to the relationship between speech naturalness and speech rate. Results of all three indicated that for PWS, the slower a speaker's rate was, the less natural speech was judged to sound. The three listener groups also showed similar trends with regard to naturalness of the stuttering versus the non-stuttering individuals. All three panels considered the speech of the non-stuttering participants more natural. EDUCATIONAL OBJECTIVES: The reader will be able to: (1) discuss the speech naturalness of people who stutter speaking under delayed auditory feedback, (2) discuss listener differences about the naturalness of people who stutter speaking under delayed auditory feedback, and (3) discuss the importance of speech rate for the naturalness of speech.     

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.     

Sensorimotor Adaptation to Violations of Temporal Contiguity

Most events are processed by a number of neural pathways. These pathways often differ considerably in processing speed. Thus, coherent perception requires some form of synchronization mechanism. Moreover, this mechanism must be flexible, because neural processing speed changes over the life of an organism. Here we provide behavioral evidence that humans can adapt to a new intersensory temporal relationship (which was artificially produced by delaying visual feedback). The conflict between these results and previous work that failed to find such improvements can be explained by considering the present results as a form of sensorimotor adaptation.     

A pilot study into a possible relationship between diet and stuttering

PurposeThere are theoretical and empirical reasons to consider a potential role for copper metabolism in the brain in how it could influence stuttering. However, a link between stuttering and dietary intake has never been researched in a systematic way. This pilot study therefore aimed to explore a possible association between ingested amounts of copper and thiamine (vitamin B1) with stuttering frequency using a double blind cross-over longitudinal paradigm.Methods19 adults who stutter between 20 and 51 years old filled out an online survey for 9 consecutive weeks. The survey consisted of self-assessed fluency and mood state scales, as well as food journals. After 4 weeks, the participants consumed either copper or thiamine supplements for 2 weeks, followed by a 1-week washout period, and another period of two weeks taking the other supplement. Formal speech assessments were done pre/post baseline and at the end of each supplement intake. Participants were not informed about the nature of the supplements during the experiment and the investigators were blinded to the order of the supplements.ResultsThe results demonstrated that copper and thiamine had no measurable effect on the amount of stuttering (self and formal assessments) but there was a moderate, significant correlation between mood state and fluency.ConclusionThe findings do not support notions of dietary influences of ingested copper or thiamine on stuttering but do provide modest support for a relationship between variations in stuttering and self-perceived anxiety.     

The differential effect of three auditory stimuli on the frequency of stuttering behaviors

In view of the frequent clinical use of external auditory stimuli in fluency building programs, the purpose of the present experiment was to compare the effects of rhythmic pacing, delayed auditory feedback, and high intensity masking noise on the frequency of stuttering by dysfluency type. Twelve normal hearing young adult stutterers completed an oral reading (approximately 250 syllables) and conversational speech task (3 min) while listening to the three auditory stimuli and during a control condition presented in random order. The results demonstrated that during oral reading all three auditory stimuli were associated with significant reductions in stuttering frequency. However, during conversational speech, only the metronome produced a significant reduction in total stuttering frequency. Individual dysfluency types were not differentially affected by the three auditory stimuli.     

Fluency-related behaviors and attitudes of 178 young stutterers

An item-by-item analysis was made of the scores of 178 five- to eighteen-year-old stutterers on the 27-item Cooper Chronicity Prediction Checklist for School-Aged Stutterers and a stuttering frequency estimate form. Results were interpreted as suggesting that male stutterers generally possess a more complex stuttering pattern than do females and that the definition as to what constitutes stuttering continues to vary significantly between parents, clinicians, and individuals labeled as stutterers.     

The relationship between anxiety, fatigue and spontaneous recovery in stuttering

There is apparently no formalized hypothesis regarding the antecedents of spontaneous recovery of stuttering. Since adaptation and recovery appear to be functionally related, antecedents of adaptation have been considered to be antecedent to spontaneous recovery. Two disparate hypotheses of adaptation which have experimental support are the anxiety hypothesis and the fatigue hypothesis. The present study was initiated to investigate the relationship of anxiety and/or fatigue, if any, to spontaneous recovery. Twenty-one subjects (stutterers) participated in four conditions. Each condition consisted of eight oral readings of a passage. The experimental variables were introduced into the respective conditions after the fifth oral reading. They were: (I) no rest, same passage; (II) rest, same passage; (III) no rest, different passage; and, (IV) rest, different passage. Palmar sweat fingerprints of anxiety were taken concurrently with the first thirty seconds of trials one, three, five, six, seven and eight for all conditions. The results of the investigation led to the conclusions that: (1) there was no necessary relationship between a change in the frequency of stuttering and a change in the anxiety level ; (2) the Hullian concepts of reactive and conditioned inhibition appeared to provide a meaningful approach to the question of spontaneous recovery of stuttering behaviour.     

Communication attitudes in children who stutter: A meta-analytic review

BackgroundThis article presents a meta-analytic review of differences in communication attitudes between children who stutter (CWS) and children who do not stutter (CWNS).MethodTo be included in this review, the studies had to include a group of CWS and CWNS between the ages of 3–18 years and a measurement of communication attitudes. The journal articles were identified by using the key words stutter*, speech disfluenc*, fluency disorder*, and stammer* cross-referenced to awareness*, reaction*, attitude*, KiddyCAT, CAT, A-19 Scale, PASS and OASES.ResultsA total of 18 studies met the inclusion criteria for this meta-analysis. The results showed that CWS exhibit more negative communication attitudes than CWNS from the preschool years. The differences between the groups increased with age, but were not influenced by gender.ConclusionThe results indicate that negative communication attitudes can be an effect of stuttering. Key issues requiring further investigation are whether communication attitudes differ as a function of age at stuttering onset and whether communication attitudes influence the development of stuttering.Educational Objectives: After reading this article, the reader will be able to: (a) summarise empirical findings with regard to the relationship between communication attitudes and childhood stuttering; (b) describe the different instruments used to measure communication attitudes; (c) discuss the relationship between communication attitudes, age and gender.     

Stuttering and sensory gating: a study of acoustic startle prepulse inhibition

It was hypothesized that stuttering may be related to impaired sensory gating, leading to overflow of superfluous disturbing auditory feedback and breakdown of the speech sequence. This hypothesis was tested using the acoustic startle prepulse inhibition (PPI) paradigm. A group of 22 adults with developmental stuttering were compared with controls regarding the degree of PPI. No significant differences were found between the stuttering adults and the control group; the groups showed similar means and distribution. Likewise, no relation between the degree of PPI and the effect of altered auditory feedback on stuttering was found. In summary, the results of the study indicate that there is no relation between stuttering and PPI.     

Resilience in people who stutter: Association with covert and overt characteristics of stuttering

PurposeRecent literature stresses the importance of resilience, as a trait, for successful coping with life’s difficulties or stressors. However, only a limited number of studies were conducted on resilience among people-who-stutter (PWS). These studies did not examine the association between resilience and the specific characteristics of stuttering. This study was, therefore, aimed to directly examine the association between resilience and measures of both the covert and overt characteristics of stuttering.MethodThirty adults who stutter completed the Connor-Davidson Resilience Scale (CD-RISC) and the Overall Assessment of Speaker’s Experience of Stuttering - Adults (OASES-A). In addition, stuttering severity of all participants was quantified using the Stuttering Severity Instrument-4 (SSI-4). The associations between all measures were examined statistically.ResultsA strong and significant association was found between the participants' scores on the CD-RISC and the OASES-A (r= -.79, p < .001). In contrast, no significant correlation was found between the participants' scores in the CD-RISC and the SSI-4 (r = .02, p > .05). Within our cohort, no significant association was observed between the participants’ gender and age and their resilience levels (p > 0.05).ConclusionThis study demonstrates the role of resilience in shaping the individual's experience with stuttering. Results also show that the individuals' resilience levels do not necessarily predict stuttering severity per se, or its overt manifestations but can predict the individuals' subjective perception of his/her stuttering. This highlights the importance of addressing and promoting resilience among PWS in stuttering therapy.     

授权型领导对员工反馈寻求行为的影响机制：领导差异化授权两阶段的调节作用

从员工直接感知的角度编制领导差异化授权问卷,并通过构建两阶段有调节的中介模型探讨了授权型领导对反馈寻求行为的影响机制与领导差异化授权在其中的调节作用。对388份问卷数据分析后发现：（1）授权型领导正向预测员工的领导认同与反馈寻求行为;（2）领导认同在授权型领导与反馈寻求行为中起中介作用;（3）领导差异化授权调节授权型领导通过领导认同对反馈寻求行为的中介作用,即调节了中介过程的第一段（授权型领导−领导认同）与第二段（领导认同−反馈寻求行为）。研究结果揭示了授权型领导影响反馈寻求行为的中介与调节效应,可为管理实践中促进反馈寻求行为提供科学参考。     

音乐与语言的关系：来自句法、语义与音调节奏感知的神经活动证据

音乐和语言加工神经基础的关系研究,近年来发展迅速,获得了越来越多的关注。“共享结构整合资源假说”主张音乐的句法加工和语言的句法加工具有较大程度的神经资源的共享。在听觉语言实验中反映句法违例的ERP ELAN与音乐句法违例引发的ERAN极为相似,唯一的区别仅在于它们的分布有所不同——ERAN就像是一个两半球对称的ELAN。而且ERAN的引发不受是否接受过音乐训练这一因素的影响,虽然音乐人被试引发的ERAN波幅更大。一些研究发现音乐语义加工的神经基础为N400和N500。前者可以由音乐和语言两种刺激引发,后者只能由音乐意义的加工引发。然而,音乐的音调感知和语言的音调感知是否共享了神经资源,却还没有确定的结论。     

Exogenous verbal response inhibition in adults who do and do not stutter

IntroductionBehavioral and questionnaire-based studies suggest that children who stutter (CWS) exhibit poorer response inhibition than children who do not stutter (CWNS). However, the behavioral findings in adults who stutter (AWS) are less unequivocal and mainly based on manual response inhibition. Further study is therefore needed, especially given the lack of studies on verbal response inhibition among these groups.MethodsThirteen AWS and 14 adults who do not stutter (AWNS) participated in a verbal stop signal task (SST) in which they were asked to read aloud six Chinese characters as fast as possible during the go-signal and ignore-signal trials and refrain from naming them during the stop-signal trials.ResultsThe two groups showed a comparable response reaction time in the go-signal and ignore-signal trial conditions. Furthermore, there were no significant differences in terms of the stop-signal reaction time (SSRT) and accuracy. However, a significant positive correlation was found between SSRT and the frequency of stuttering in conversation but not in reading.ConclusionCurrent findings seem to provide additional support that exogenously triggered response inhibition among AWS does not differ from AWNS. The association between stuttering frequency and SSRT seems to suggest that individuals with more severe stuttering in conversational speech have reduced exogenous response inhibition. However, this finding needs to be further explored in future studies using different measures of stuttering severity.     

Rethinking covert stuttering

PurposeThe experience of passing as fluent, also called covert stuttering, has been uncritically framed as an inherently negative pursuit. Historically passing has been understood as a repression of one’s true, authentic self in response to either psychological distress or social discrimination. The authors of this paper seek a more nuanced understanding of passing. We ask, how must a person relate to herself in order to pass as fluent?MethodologyThis is a qualitative research study in which the authors utilized the ethical theories of philosopher Michel Foucault to contextualize data obtained from semi-structured interviews with nine participants who pass as fluent.ResultsRather than a repression of an authentic self our data suggests passing is more usefully understood as a form of resistance by people who stutter to a hostile society. Participants learned from experiences of delegitimization that their stuttering had ethical ramifications. Consequently, they used a variety of self-forming practices to pass and thereby achieve the privileges that come with perceived able-bodiedness.ConclusionPassing as fluent is not an inauthentic form of stuttering but a form of stuttering that is produced through the use of specific technologies of communication. These technologies of communication are constituted by the unique ethical relationship of the person who stutters with herself. Passing can be understood as an active form of resistance rather than a passive form of repression. By theorizing passing as fluent as an ethical relationship, we open up the possibility of changing the relationship and performing it differently.     

Oral/manual motor reaction times and delayed auditory feedback disturbances among normally speaking females

Research has indicated that stuttering and nonstuttering groups can be differentiated on the basis of certain motor reaction time variables. This study evaluated the manual and oral reaction times to a 1000 Hz stimulus tone in 39 normally speaking college females. Speech disfluencies of the subjects (Ss) were identified by a four-judge panel and correlated with reaction time scores. Although no significant correlations were obtained, it was observed that Ss with faster oral and manual reaction times tended to have more disfluencies under delayed auditory feedback.     

Phonological priming in adults who stutter

The purpose of this study was to compare the speed of phonological encoding between adults who stutter (AWS) and adults who do not stutter (ANS). Fifteen male AWS and 15 age- and gender-matched ANS participated in the study. Speech onset latency was obtained for both groups and stuttering frequency was calculated for AWS during three phonological priming tasks: (1) heterogeneous, during which the participants' single-word verbal responses differed phonemically; (2) C-homogeneous, during which the participants' response words shared the initial consonant; and (3) CV-homogeneous, during which the participants' response words shared the initial consonant and vowel. Response words containing the same C and CV patterns in the two homogeneous conditions served as phonological primes for one another, while the response words in the heterogeneous condition did not. During each task, the participants produced a verbal response after being visually presented with a semantically related cue word, with cue-response pairs being learned beforehand. The data showed that AWS had significantly longer speech onset latency when compared to ANS in all priming conditions, priming had a facilitating effect on word retrieval for both groups, and there was no significant change in stuttering frequency across the conditions for AWS. This suggests that phonological encoding may play no role, or only a minor role, in stuttering. EDUCATIONAL OBJECTIVES: The reader will be able to: (1) describe previous research paradigms that have been used to assess phonological encoding in adults and children who stutter; (2) explain performance similarities and differences between adults who do and do not stutter during various phonological priming conditions; (3) compare the present findings to past research that examined the relationship between phonological encoding and stuttering.