Language and disfluency variables in normal speaking children from discrete chronological age groups

Thirty male and female children from three chronological age groups were compared on Developmental Sentence Score, total words spoken in a language sample, total disfluency, and eight specific disfluency subtypes. Analyses were performed to determine in differences existed among the three age groups, between sexes, and whether language and disfluency were related. No sex differences in either language or disfluency were found. Total disfluency showed only a slight decrease with an increase in chronological age between 4 and 8 years. This suggests that the major disfluency decrease must occur subsequent to age 8. Although the total disfluency changed minimally between ages 4 and 8, some of the disfluency subtypes shifted considerably. Older children were almost as disfluent as younger children, but the topography of their disfluency was different. No significant relationship was found between the disfluency and language variables studied.     

Disfluency characteristics of 2-, 4-, and 6- yr-old males

Fluency characteristics of 36 nonstuttering males aged 2, 4, and 6 yr are presented in terms of patterns of disfluency and relationships among disfluency variables. The most frequently occuring disfluency types at each age level were revision-incomplete phrase and interjections; the least noted type was part-word repetitions for 2- and 4-yr olds and disrhythmic phonations for 6-yr-olds. Patterns of disfluency appear to be similar at all age levels studied, except that the 2-yr-old pattern showed greater magnitudes in various disfluency types. A range exists in the relationships among individual disfluency types, from moderately strong relationships between, for example, revision-incomplete phrase and interjections to lack of linear relationships between, for example, interjections and phrase repetitions. A linguistic factor may be strong within certain disfluency types. e.g., revision-incomplete phrase, interjections, and word repetitions, whereas a motor factor may be operative in others, e.g., part-word repetitions and disrhythmic phonations.     

Listener ratings of severity for specific disfluency types in children

This study investigated whether some types of disfluency are perceived as more severe than others and if listener groups differ in their perception of severity for some disfluency types. Three normal speaking children were trained to produce eight types of disfluency and one sample of fluency. The experimental tape, consisting of three examples for each of the eight disfluency types and of fluency, was presented auditorily to 40 judges divided into four groups of 10 each: parents of stutterers, parents of nonstutterers, speech clinicians, and elementary school teachers. The judges rated the disfluency and fluency on a 15-point severity continuum, divided into four nominal categories of Fluent, Normal Disfluency, Mild Stuttering, Moderate Stuttering, and Severe Stuttering. Results showed that although listener groups did not significantly differ in their severity ratings, the specific types of disfluency did differ significantly. The type of disfluency emitted by a speaker is apparently more salient in perceiving and judging disfluency than the type of listener making the judgment.     

Disfluencies and rate of speech in young adult nonstutterers

The purpose of this study was to identify disfluency levels and rates of speech in young adults while they were being interviewed and during reading. Fifty undergraduate students (25 males and 25 females) served as subjects. Each was recorded individually while being interviewed and while reading a standard clinical passage. Percentage of disfluency, using eight disfluency categories, and rates of speech were obtained for all conditions. Results provide information that allows for comparison of post-therapy stutterers with nonstutterers during a clinical interview.     

Would disfluency by any other name still be disfluent? Examining the disfluency effect with cursive handwriting

When exposed to words presented under perceptually disfluent conditions (e.g., words written in Haettenschweiler font), participants have difficulty initially recognizing the words. Those same words, though, may be better remembered later than words presented in standard type font. This counterintuitive finding is referred to as the disfluency effect. Evidence for this disfluency effect, however, has been mixed, suggesting possible moderating factors. Using a recognition memory task, level of disfluency was examined as a moderating factor across three experiments using a novel cursive manipulation that varied on degree of legibility (easy-to-read cursive vs. hard-to-read cursive). In addition, list type and retention interval between study and test were manipulated. Across all three experiments, cursive words engendered better memory than type-print words. This memory effect persisted across varied list designs (blocked vs. mixed) and a longer (24-hour) retention interval. A small-scale meta-analysis across the three experiments suggested that the cursive disfluency effect is moderated by level of disfluency: easy-to-read cursive words tended to be better remembered than hard-to-read cursive words. Taken together, these results challenge extant accounts of the disfluency effect. The theoretical and practical implications of these findings are discussed.     

Disfluency of nonstuttering children in relation to specific measures of language,reading, and mental maturity

Speech samples from 92 first-grade children were quantified on the basis of disfluency types and judges' ratings of language level. Intelligence and reading scores were also obtained for each subject. Correlational analysis indicated that the measures of language performance, intelligence, and reading ability used in this study were not highly and significantly associated with frequency of disfluency whether considered by individual type, type combinations, or total disfluency.     

A Call for an Unbiased Search for Moderators in Disfluency Research: Reply to Oppenheimer and Alter (2014)

In a commentary to our article, Oppenheimer and Alter stressed the importance of searching for moderators in disfluency research. We agree, but we would like to clarify two issues. First, unlike Oppenheimer and Alter, we assume that learner characteristics might indeed moderate the effects of disfluency. Second, conclusions concerning the impact of disfluency in educational settings might be biased because of the file‐drawer problem. To counteract this possibility, we want to encourage other researchers to publish their studies––regardless of whether they found (positive) effects of disfluency or not. Until then, any recommendation concerning the use of disfluency as an educational intervention seems premature.     

The relationship between age and frequency of disfluency in preschool children

The frequencies of nine types of disfluency, including silent pauses, were studied in 60 nonstuttering males, 3.5 and 5 yr-of-age. The younger children evidenced significantly higher rates of part word, word, and phrase repetitions, incomplete phrases, and disrhythmic phonations. The older children demonstrated significantly more grammatical pauses. The two groups did not differ in the frequency of interjections, ungrammatical pauses, and revisions. The most powerful discriminating category between the two age groups was phrase repetition. The results are compared with findings from other recent investigations of disfluency in nonstuttering preschool males. Possible explanations for the discrepancies among the various investigations and for the high degree of variability in disfluency reported in the literature are proposed. The results of this investigation suggest that nonstuttering children begin to show more adult-like disfluency patterns toward the later preschool years.     

Disfluency Meets Cognitive Load in Multimedia Learning: Does Harder‐to‐Read Mean Better‐to‐Understand?

In a series of four experiments, we examined the impact of disfluency in multimedia learning by testing contrasting predictions derived from disfluency theory and cognitive load theory against each other. Would a less legible text be beneficial to learning when accompanied by pictures, and what would be the role of less legible pictures? Students (N = 308) learned with text and pictures that were either easy‐to‐read (i.e., fluent) or harder‐to‐read (i.e., disfluent) about how a toilet flush works (Experiments 1–3) and about how lightning develops (Experiment 4). In line with disfluency theory, a disfluent text led to better performance in the transfer test and to more invested mental effort in Experiment 1. However, these beneficial effects could not be replicated in Experiments 2, 3, and 4, leaving open questions regarding the stability and generalizability of the disfluency effect, and thus raising concerns regarding its impact for educational practice. Copyright © 2014 John Wiley & Sons, Ltd.     

Fluency and disfluency; Illusion and identification

At approximately the same time, two lines of research have studied disfluencies from different orientations—one in stuttering and the other in normal speech. In certain important respects the findings of these separate lines differ. Resolution of these differences, which is particularly important for understanding stuttering in its relation to disfluency and fluency, has been precluded because the two research areas have remained essentially isolated from each other.Progress in understanding stuttering would benefit considerably from adequate attention to the findings of research on disfluency in normal speech, which already has yielded a substantial amount of information pertinent to the concepts of fluency and disfluency; the nature and extent of disfluency; the linguistic and cognitive significance of disfluencies; and the differentiation between normal and abnormal disfluency.     

背景图相关度与知觉流畅性对意义材料学习的影响

可取难度理论和不流畅理论认为不流畅加工可促进学习,认知负荷理论则认为知觉不流畅所激发的额外认知负荷可能阻碍学习。研究采用2（知觉流畅性：流畅,不流畅）×3（背景图相关度：相关背景图、无关背景图和空白背景）被试间实验设计,考察学习意义材料时认知负荷（通过插入的背景图控制）与知觉流畅性的相互作用。结果发现：（1）知觉流畅性的主效应显著,知觉流畅时的学习成绩显著高于知觉不流畅时的成绩;背景图相关度的主效应显著,相关背景图条件下的成绩显著高于空白背景和无关背景图。（2）知觉流畅性与背景图相关度的交互作用显著,在知觉流畅条件下,呈现相关背景图的得分显著高于空白背景和无关背景图,后二者无显著差异;知觉不流畅条件下,三者间无显著差异。研究结果表明,在知觉流畅的条件下插入相关背景图有利于意义材料的学习;该结果支持认知负荷理论。     

Qualitative and quantitative differences and patterns of variability in disfluencies emitted by preschool stutterers and nonstutterers during dyadic conversations

Disfluencies produced by 24 young stuttering and nonstuttering boys (4 to 5 years old) interacting in three dyadic sessions were analyzed. Each child interacted with his own mother, an unfamiliar mother of a stutterer, and an unfamiliar mother of a nonstutterer. Significant quantitative and qualitative differences were found in the number and types of disfluencies emitted by the two groups of children. Stuttering children with more severe disfluency problems differed quantitatively from those with less severe problems. Total frequency of disfluency was highly consistent for both groups of children. Only two disfluency types (tense pauses and whole-word repetitions) showed significant variability across sessions. This research demonstrates the feasibility of differential diagnosis of young stuttering children.     

Disfluency in dialogue: an intentional signal from the speaker?

Disfluency is a characteristic feature of spontaneous human speech, commonly seen as a consequence of problems with production. However, the question remains open as to why speakers are disfluent: Is it a mechanical by-product of planning difficulty, or do speakers use disfluency in dialogue to manage listeners' expectations? To address this question, we present two experiments investigating the production of disfluency in monologue and dialogue situations. Dialogue affected the linguistic choices made by participants, who aligned on referring expressions by choosing less frequent names for ambiguous images where those names had previously been mentioned. However, participants were no more disfluent in dialogue than in monologue situations, and the distribution of types of disfluency used remained constant. Our evidence rules out at least a straightforward interpretation of the view that disfluencies are an intentional signal in dialogue.     

It's the way that you, er, say it: hesitations in speech affect language comprehension

Everyday speech is littered with disfluency, often correlated with the production of less predictable words (e.g., Beattie & Butterworth [Beattie, G., & Butterworth, B. (1979). Contextual probability and word frequency as determinants of pauses in spontaneous speech. Language and Speech, 22, 201-211.]). But what are the effects of disfluency on listeners? In an ERP experiment which compared fluent to disfluent utterances, we established an N400 effect for unpredictable compared to predictable words. This effect, reflecting the difference in ease of integrating words into their contexts, was reduced in cases where the target words were preceded by a hesitation marked by the word er. Moreover, a subsequent recognition memory test showed that words preceded by disfluency were more likely to be remembered. The study demonstrates that hesitation affects the way in which listeners process spoken language, and that these changes are associated with longer-term consequences for the representation of the message.     

The effect of instructional bias on listener ratings of specific disfluency types in children

This study evaluated the influence of instructional bias on severity ratings of children's disfluencies. Normal speaking children were trained to simulate specific types of disfluency and severity judgments were made by judges who had been exposed to instructional bias. The 75 judges who participated in the study were divided into three groups of 25 each and were given a bias “toward stuttering,” bias “toward fluency,” and a “neutral” bias toward neither perceptual set. Both univariate and multivariate analyses were employed for data analysis.Although predictable differences were found between the specific types of speech disfluency, no significant differences were found for the experimental bias conditions. These findings, based on molecular analyses, differ from previous results based on molar speech samples. Molecular approaches to understanding the nature of stuttering were found to be powerful modes of assessment, and it is suggested that the type of disfluency emitted by children may be more important than the instructional bias or perceptual set of the listener.     

Pause loci in stuttered and normal speech

The mainstream of research comparing types of disfluency in stuttered and normal speech has typically omitted consideration of pause. In contrast, psycholinguisticresearch addressed to disfluency in normal speech alone has revealed the salience of pause in the study of fluency/disfluency. The research reported here, which focused on the antecedents and sequelae of filled pauses, revealed substantial differences in pattern of pause occurrence between stuttered and normal speech samples obtained from 20 matched subjects. The results are discussed in reference to relevant findings from the research on pause in normal speech.     

Measurement of speech disfluency through magnitude estimation and interval scaling

The purpose was to assess whether equal-appearing interval or magnitude-estimation scaling resulted in a data set with a closer correlation to the physical stimuli, made up of speech samples with varying amounts of disfluency. 20 young adults completed two tasks. In Task 1, subjects used a 7-point equal-appearing interval scale to rate the disfluency of 10 speech samples having varying within sentence pause, presented randomly at 65 dB SPL. In Task 2, subjects used magnitude-estimation scaling to rate these stimuli, presented in a randomized order. Analysis showed significantly high correlations for both scaling techniques and the speech stimuli (Spearman rho=.90 and 1.00, respectively). It appears that subjects can use either scaling technique to rate accurately varied speech disfluency.     

Disfluencies in cluttered speech

The purpose of this study was to examine the nature and frequency of occurrence of disfluencies, as they occur in singletons and in clusters, in the conversational speech of individuals who clutter compared to typical speakers. Except for two disfluency types (revisions in clusters, and word repetitions in clusters) nearly all disfluency types were virtually indistinguishable in frequency of occurrence between the two groups. These findings shed light on cluttering in several respects, foremost of which is that it provides documentation on the nature of disfluencies in cluttering. Findings also have implications for our understanding of the relationship between cluttering and typical speech, cluttering and stuttering, the Cluttering Spectrum Hypothesis, as well as the Lowest Common Denominator definition of cluttering. EDUCATIONAL OBJECTIVES: At the end of this activity the reader will be able to: (a) identify types of disfluency associated with cluttered speech; (b) contrast disfluencies in cluttered speech with those associated with stuttering; (c) compare the disfluencies of typical speakers with those of cluttering; (d) explain the perceptual nature of cluttering.     

Vocal changes in stutterers and nonstutterers during monotoned speech

For years, reports have circulated that stutterers experience marked decrements in their stuttering when they speak or read in monotone. Wingate has suggested that the ameliorative effects of various novel speaking conditions on stuttering can be attributed to modifications in vocalization induced by such conditions. The present study was conducted to see whether this explanation would extend to monotoned speech as well. Ten teenage and adult stutterers and 10 normal speakers were tested in control and monotone reading conditions. Dependent measures were the frequencies of disfluency and stuttering, fundamental frequency, fundamental frequency standard deviation, vocal SPL, vocal SPL standard deviation, and fluent reading rate. Only within-group statistical comparisons were made, because members of the two groups could not be matched pairwise along critical vocal parameters. The major findings of this study indicated that across the two conditions, both groups significantly reduced their fundamental frequency, fundamental frequency standard deviation, vocal SPL and vocal SPL standard deviation. Only the stutterers exhibited a significant decrement in disfluency and stuttering. The normals did not evince enough disfluency in the control condition for a reduction to occur during monotoning. Neither group effected a reduction in fluent reading rates. These and other findings and interpretations are discussed relative to Wingate's modified vocalization hypothesis.     

Fortune favors the bold (and the Italicized): effects of disfluency on educational outcomes

Previous research has shown that disfluency – the subjective experience of difficulty associated with cognitive operations – leads to deeper processing. Two studies explore the extent to which this deeper processing engendered by disfluency interventions can lead to improved memory performance. Study 1 found that information in hard-to-read fonts was better remembered than easier to read information in a controlled laboratory setting. Study 2 extended this finding to high school classrooms. The results suggest that superficial changes to learning materials could yield significant improvements in educational outcomes.