Age of acquisition and repetition priming effects on picture naming of children who do and do not stutter

Exploring the Activation of Target Words in Picture Naming in Children Who Stutter: Evidence From Event-Related Potentials

PURPOSE

Target word activation in picture naming was explored in children who stutter (CWS) and typically fluent children (TFC) using event-related potentials (ERPs).

METHOD

A total of 18 CWS and 16 TFC completed a task combining picture naming and probe word identification. On each trial, a picture-to-be-named was followed by an auditory probe word-to-be-identified; the probe was identical (Identity condition) or Unrelated to the picture name. ERPs were recorded from probe onset. Attenuation of the N400 ERP component was predicted to Identity versus Unrelated trials (N400 priming). Between-groups differences in amplitude, timing, and topography of N400 priming were explored.

RESULTS

Naming was more accurate on Identity versus Unrelated trials. Probe word identification accuracy was not affected by Condition. N400 priming was detected, indicating that self-generated picture names facilitated semantic processing of identical probes. This effect was larger in amplitude in CWS versus TFC. Unexpectedly, an N400-preceding, frontally maximal, positive-going ERP component-associated with expectancy processing-was larger in amplitude to Unrelated versus Identity trials. This effect was smaller in CWS versus TFC.

CONCLUSIONS

A larger N400 priming effect in CWS versus TFC reflects a tendency toward more extensive semantic processing in picture naming in CWS. A smaller Condition effect on frontally maximal, positive-going, N400-preceding ERP activity in CWS versus TFC indicates a reduced ability to form expectancies about the lexical and/or phonological identity of probe words in CWS. Both effects may point to inefficient activation of target words in picture naming in CWS.

Similarities and differences in the lexical-grammatical relation of young dual language learners with and without specific language impairment

This study examines the lexical-grammatical relation within and across in preschool Latino dual language learners (DLLs) with and without specific language impairment (SLI) using language-specific vocabulary and conceptual lexical-semantic skills. The participants were sixty-one typically developing (TD) Spanish-English speaking DLLs and seventy-four DLLs with SLI from low-income households. Standardized and researcher developed assessment tools were used to measure vocabulary, semantics, and grammar in both Spanish and English. Cross-sectional data were analyzed using hierarchical linear regressions to determine the nature of the lexical-grammatical association within and across languages. The study found significant within-language relations between measures of vocabulary and grammar for both groups. Conceptual vocabulary was a significant predictor for English grammar in both groups. For the SLI group only, both English and Spanish vocabulary scores significantly predicted English grammar and bilingual semantics scores predicted Spanish grammar. These findings underscore the role of language-specific vocabulary on grammatical development and suggest the presence of bilingual bootstrapping in DLLs. However, the degree and nature of cross-linguistic associations vary by language ability and language proficiency. The role of age and nonverbal cognition and clinical implications are also discussed.

Phonological and Semantic Contributions to Verbal Short-Term Memory in Young Children With Developmental Stuttering

Purpose The purpose of this study was to examine the verbal short-term memory skills of children who stutter (CWS) and children who do not stutter (CWNS) in 2 experiments, focusing on the influence of phonological and semantic similarity. Method Participants were 42 CWS and 42 CWNS between the ages of 3;0 and 5;11 (years;months). In Experiment 1, children completed the phonological similarity task, in which they listened to lists of phonologically similar and dissimilar words and then repeated them when signaled to do so. In Experiment 2, children completed another forward span task, the semantic category task, which is similar to the phonological similarity task, except that it consisted of lists of semantically homogeneous and heterogeneous words. Main dependent variables were cumulative memory span, proportion of errors by type, and speech reaction time (SRT) for correct responses. Results The CWS exhibited significantly shorter memory spans for phonologically dissimilar words and were less affected by the phonological qualities of the words than the CWNS in Experiment 1, based on the findings of both between-groups and within-group analyses. In Experiment 2, although the groups did not differ in their performance in either condition, within-group analyses revealed that the CWNS benefitted from semantic similarity, whereas the CWS did not. The between-groups difference in absolute difference scores, however, did not reach significance. The CWS produced more omissions and false alarms than the CWNS in both experiments, but the 2 groups of children were otherwise comparable in SRT, although the CWS exhibited overall faster SRT than the CWNS in Experiment 2. Conclusions Verbal short-term memory is one domain-general cognitive process in which CWS display weakness relative to typically fluent peers. These weaknesses are likely due, in part, to differences in phonological and, perhaps, semantic processing of words to aid memory.

Short-Term Memory, Inhibition, and Attention in Developmental Stuttering: A Meta-Analysis

Purpose

This study presents a meta-analytic review of differences in verbal short-term memory, inhibition, and attention between children who stutter (CWS) and children who do not stutter (CWNS).

Method

Electronic databases and reference sections of articles were searched for candidate studies that examined verbal short-term memory, inhibition, and attention using behavioral and/or parent report measures. Twenty-nine studies met the eligibility criteria, which included, among other things, children between the ages of 3 and 18 years and the availability of quantitative data for effect size calculations. Data were extracted, coded, and analyzed, with the magnitude of the difference between the 2 groups of children being estimated using Hedge's g (Hedges & Olkin, 1985).

Results

Based on the random-effects model (Hunter & Schmidt, 2004), findings revealed that CWS scored lower than CWNS on measures of nonword repetition (Hedges' g = -0.62), particularly at lengths of 2 and 3 syllables (Hedges' g = -0.62 and - 0.50, respectively), and forward span (Hedges' g = -0.40). Analyses further revealed that the parents of CWS rated their children as having weaker inhibition (Hedges' g = -0.44) and attentional focus/persistence (Hedges' g = -0.36) skills than the parents of CWNS, but there were no significant differences between CWS and CWNS in behavioral measures of inhibition and attention.

Conclusion

The present findings were taken to suggest that cognitive processes are important variables associated with developmental stuttering.

The effect of phonetic complexity on the speed of single-word productions in adults who do and do not stutter

PURPOSE

The purpose of this study was to investigate the influence of phonetic complexity as measured by the Word Complexity Measure (WCM) on the speed of single-word production in adults who do (AWS, n=15) and do not stutter (AWNS, n=15).

METHOD

Participants were required to name pictures of high versus low phonetic complexity and balanced for lexical properties. Speech reaction time was recorded from initial presentation of the picture to verbal response of participant for each word type. Accuracy and fluency were manually coded for each production.

RESULTS

AWS named pictures significantly slower than AWNS, but there were no significant differences observed in response latency when producing word of high versus low phonetic complexity as measured by the WCM.

CONCLUSION

Findings corroborate past research of overall slowed picture naming latencies in AWS, compared to AWNS. Findings conflict with data that suggest that the phonetic complexity of words uniquely compromises the speed of production in AWS. The potential interaction between lexical and phonetic factors on single-word production within each group are discussed.

Explicit and Implicit Verbal Response Inhibition in Preschool-Age Children Who Stutter

PURPOSE

The purpose of this study was to examine (a) explicit and implicit verbal response inhibition in preschool children who do stutter (CWS) and do not stutter (CWNS) and (b) the relationship between response inhibition and language skills.

METHOD

Participants were 41 CWS and 41 CWNS between the ages of 3;1 and 6;1 (years;months). Explicit verbal response inhibition was measured using a computerized version of the grass-snow task (Carlson & Moses, 2001), and implicit verbal response inhibition was measured using the baa-meow task. Main dependent variables were reaction time and accuracy.

RESULTS

The CWS were significantly less accurate than the CWNS on the implicit task, but not the explicit task. The CWS also exhibited slower reaction times than the CWNS on both tasks. Between-group differences in performance could not be attributed to working memory demands. Overall, children's performance on the inhibition tasks corresponded with parents' perceptions of their children's inhibition skills in daily life.

CONCLUSIONS

CWS are less effective and efficient than CWNS in suppressing a dominant response while executing a conflicting response in the verbal domain.

Different Loci of Semantic Interference in Picture Naming vs. Word-Picture Matching Tasks

Naming pictures and matching words to pictures belonging to the same semantic category impairs performance relative to when stimuli come from different semantic categories (i.e., semantic interference). Despite similar semantic interference phenomena in both picture naming and word-picture matching tasks, the locus of interference has been attributed to different levels of the language system - lexical in naming and semantic in word-picture matching. Although both tasks involve access to shared semantic representations, the extent to which interference originates and/or has its locus at a shared level remains unclear, as these effects are often investigated in isolation. We manipulated semantic context in cyclical picture naming and word-picture matching tasks, and tested whether factors tapping semantic-level (generalization of interference to novel category items) and lexical-level processes (interactions with lexical frequency) affected the magnitude of interference, while also assessing whether interference occurs at a shared processing level(s) (transfer of interference across tasks). We found that semantic interference in naming was sensitive to both semantic- and lexical-level processes (i.e., larger interference for novel vs. old and low- vs. high-frequency stimuli), consistent with a semantically mediated lexical locus. Interference in word-picture matching exhibited stable interference for old and novel stimuli and did not interact with lexical frequency. Further, interference transferred from word-picture matching to naming. Together, these experiments provide evidence to suggest that semantic interference in both tasks originates at a shared processing stage (presumably at the semantic level), but that it exerts its effect at different loci when naming pictures vs. matching words to pictures.

Real-time processing in picture naming in adults who stutter: ERP evidence

OBJECTIVE

The aim was to compare real-time language/cognitive processing in picture naming in adults who stutter (AWS) versus typically-fluent adults (TFA).

METHODS

Participants named pictures preceded by masked prime words. Primes and target picture labels were identical or mismatched. Priming effects on naming and picture-elicited ERP activity were analyzed. Vocabulary knowledge correlations with these measures were assessed.

RESULTS

Priming improved naming RTs and accuracy in both groups. RTs were longer for AWS, and correlated positively with receptive vocabulary in TFA. Electrophysiologically, posterior-P1 amplitude negatively correlated with expressive vocabulary in TFA versus receptive vocabulary in AWS. Frontal/temporal-P1 amplitude correlated positively with expressive vocabulary in AWS. Identity priming enhanced frontal/posterior-N2 amplitude in both groups, and attenuated P280 amplitude in AWS. N400 priming was topographically-restricted in AWS.

CONCLUSIONS

Results suggest that conceptual knowledge was perceptually-grounded in expressive vocabulary in TFA versus receptive vocabulary in AWS. Poorer expressive vocabulary in AWS was potentially associated with greater suppression of irrelevant conceptual information. Priming enhanced N2-indexed cognitive control and visual attention in both groups. P280-indexed focal attention attenuated with priming in AWS only. Topographically-restricted N400 priming suggests that lemma/word form connections were weaker in AWS.

SIGNIFICANCE

Real-time language/cognitive processing in picture naming operates differently in AWS.

Lexical priming in fluent and with developmental stuttering children

PURPOSE

To examine the possible relationship between lexical variables (categorization and naming) and developmental stuttering.

METHODS

Thirty Brazilian Portuguese speaking children with ages ranging from 7 to 9 years and 11 months participated in the study. We applied a lexical priming paradigm to experimentally investigate whether children with developmental stuttering (Research Group) differed from their fluent peers (Control Group), with respect to reaction time in three conditions - control (without prime); semantically related prime, and semantically independent prime - of two experimental tasks: categorization and naming of the target stimulus.

RESULTS

No difference between groups was observed in reaction time on the categorization task. However, there was a condition effect showing that, for both groups, reaction time was shorter in the semantically related prime condition when compared to the no prime condition. In the naming task, a between-group difference was observed in reaction time, indicating a longer reaction time in the Research Group than the Control Group. There was no condition effect on naming, i.e. the Research Group showed slower reaction time regardless of prime type.

CONCLUSIONS

The results confirm the hypothesis that, in children with developmental stuttering, readiness in motor programming of speech is slowed when compared to fluent children. There is no difference between groups when the lexical function does not require speech readiness.

Socioeconomic status, parental education, vocabulary and language skills of children who stutter

PURPOSE

The purpose of this project was to investigate the possible relation between standardized measures of vocabulary/language, mother and father education, and a composite measure of socioeconomic status (SES) for children who do not stutter (CWNS) and children who stutter (CWS).

METHODS

Participants were 138 CWNS and 159 CWS between the ages of 2;6 and 6;3 and their families. The Hollingshead Four Factor Index of Social Position (i.e., Family SES) was used to calculate SES based on a composite score consisting of weighted values for paternal and maternal education and occupation. Statistical regression analyses were conducted to investigate the relation between parental education and language and vocabulary scores for both the CWNS and CWS. Correlations were calculated between parent education, Family SES, and stuttering severity (e.g., SSI-3 score, % words stuttered).

RESULTS

Results indicated that maternal education contributed the greatest amount of variance in vocabulary and language scores for the CWNS and for participants from both groups whose Family SES was in the lowest quartile of the distribution. However, paternal education generally contributed the greatest amount of variance in vocabulary and language scores for the CWS. Higher levels of maternal education were associated with more severe stuttering in the CWS.

CONCLUSION

Results are generally consistent with existing literature on normal language development that indicates maternal education is a robust predictor of the vocabulary and language skills of preschool children. Thus, both father and mothers' education may impact the association between vocabulary/language skills and childhood stuttering, leading investigators who empirically study this association to possibly re-assess their participant selection (e.g., a priori control of parental education) and/or data analyses (e.g., post hoc covariation of parental education).

LEARNING OUTCOMES

The reader will be able to: (a) describe the influence of socioeconomic status on the development of vocabulary and language for children who do and do not stutter; (b) discuss the contribution of maternal education on vocabulary and language development; (c) describe possible reasons why paternal education contributes in unique ways to the vocabulary and language development of children who stutter as well as stuttering severity; and (d) explain possible reasons why socioeconomic status is an important variable for describing language related findings in young children.

The characteristics of Chinese orthographic neighborhood size effect for developing readers

Orthographic neighborhood size (N size) effect in Chinese character naming has been studied in adults. In the present study, we aimed to explore the developmental characteristics of Chinese N size effect. One hundred and seventeen students (40 from the 3^rd grade with mean age of 9 years; 40 from the 5^th grade with mean age of 11 years; 37 from the 7^th grade with mean age of 13 years) were recruited in the study. A naming task of Chinese characters was adopted to elucidate N-size- effect development. Reaction times and error rates were recorded. Results showed that children in the 3^rd grade named characters from large neighborhoods faster than named those from small neighborhoods, revealing a facilitatory N size effect; the 5^th graders showed null N size effect; while the 7^th graders showed an inhibitory N size effect, with longer reaction times for the characters from large neighborhoods than for those from small neighborhoods. The change from facilitation to inhibition of neighborhood size effect across grades suggested the transition from broadly tuned to finely tuned lexical representation in reading development, and the possible inhibition from higher frequency neighbors for higher graders.

Do we really gesture more when it is more difficult?

Representational co-speech gestures are generally assumed to be increasingly produced in more difficult compared with easier verbal tasks, as maintained by theories suggesting that gestures arise from processing difficulties during speech production. However, the gestures-as-simulated-action framework proposes that more representational gestures are produced with stronger rather than weaker mental representations that are activated in terms of mental simulation in the embodied cognition framework. We tested these two conflicting assumptions by examining verbal route descriptions that were accompanied by spontaneous directional gestures. Easy descriptions with strong activation were accompanied more often by gestures than difficult descriptions with weak activation. Furthermore, only gesture-speech matches-but not gesture-picture matches-were increasingly produced with difficult lateral directions compared with easy nonlateral directions. We argue that lateral gesture-speech matches underlie stronger activated mental representations in mental imagery. Thus, all results are in line with the gestures-as-simulated-action framework and provide evidence against the view that gestures result from processing difficulties.

Stuttering and language ability in children: questioning the connection

PURPOSE

This article explains why it is reasonable to question the view that stuttering and language ability in children are linked-the so-called "stuttering-language connection."

METHOD

Studies that focused on syntactic, morphologic, and lexical development in children who stutter (CWS) are examined for evidence to support the following claims: (a) that CWS, as a group, are more likely to have disordered or weak language skills ("language deficits") than children who do not stutter (CWNS); (b) that language deficits play a causal role in the onset of stuttering; and (c) that stuttering, over time, restricts children's language development.

RESULTS

Analysis of the evidence suggests that CWS, like CWNS, show the full range of language abilities (high, average, low); that language deficits are not associated with stuttering onset or persistence; and that stuttering has little or no impact on language development.

CONCLUSIONS

A connection between stuttering and language ability was not supported. An alternative perspective is that CWS have a compromised motor control system that makes it difficult for them to move forward in speech and that the tie to language lies not in a deficient linguistic system but in difficulty expressing the intended meaning via a fully functional speech system.

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.

Lexical and phonological effects in early word production

PURPOSE

This study examines the influence of word frequency, phonological neighborhood density (PND), age of acquisition (AoA), and phonotactic probability on production variability and accuracy of known words by toddlers with no history of speech, hearing, or language disorders.

METHOD

Fifteen toddlers between 2;0 (years;months) and 2;5 produced monosyllabic target words varying in word frequency, PND, AoA, and phonotactic probability. Phonetic transcription was used to determine (a) whole-word variability and (b) proportion of whole-word proximity (PWP; Ingram, 2002) of each target word produced.

RESULTS

Results show a significant effect of PND on PWP and variability (words from dense neighborhoods had higher PWP and lower variability than those from sparse neighborhoods), a significant effect of word frequency on variability (high-frequency words were less variable) but not proximity, and a significant effect of AoA on proximity (earlier acquired words had lower PWP) but not variability.

CONCLUSIONS

Results provide new information regarding the role that lexical and phonological factors play in the speech of young children; specifically, several factors are identified that influence variability of production. Additionally, by examining lexical and phonological factors simultaneously, the current study isolates differential effects of the individual factors. Implications for our understanding of emerging phonological representations are discussed.

Language abilities of children who stutter: a meta-analytical review

PURPOSE

To identify, integrate, and summarize evidence from empirical studies of the language abilities of children who stutter (CWS) and children who do not stutter (CWNS).

METHOD

Candidate studies were identified through electronic databases, the tables of contents of speech-language journals, and reference lists of relevant articles and literature reviews. The 22 included studies met the following criteria: studied both children who did and did not stutter between ages 2;0 (years;months) and 8;0, and reported norm-referenced language measures and/or measures from spontaneous language samples amenable to effect size calculation. Data were extracted using a coding manual and were assessed by application of general and specialized analytical software. Mean difference effect size was estimated using Hedges's g (Hedges, 1982).

RESULTS

Findings indicated that CWS scored significantly lower than CWNS on norm-referenced measures of overall language (Hedges's g = -0.48), receptive (Hedges's g = -0.52) and expressive vocabulary (Hedges's g = -0.41), and mean length of utterance (Hedges's g = -0.23).

CONCLUSIONS

Present findings were taken to suggest that children's language abilities are potentially influential variables associated with childhood stuttering.

The integrity of anticipatory coarticulation in fluent and non-fluent tokens of adults who stutter

This article analysed the acoustic structure of voiced stop + vowel sequences in a group of persons who stutter (PWS). This phonetic unit was chosen because successful production is highly dependent on the differential tweaking of right-to-left anticipatory coarticulation as a function of stop place. Thus, essential elements of both speech motor planning and execution can be parsimoniously assessed. Five adult PWS read three passages 3 times in a randomised order. These passages contained an overabundance of words beginning with initial [bV], [dV] and [gV] sequences. Digital audio and visual recordings were analysed to first identify fluent and stuttered target words, which were then spectrally analysed to yield locus equation (LE) regression plots. The slope of the LE regression function directly indexes the coarticulatory extent of the vowel's influence on the preceding stop consonant. The PWS revealed LE parameters falling within the normal ranges based on previously documented data obtained from fluent speakers. Theoretical considerations of possible underlying factors responsible for stuttering disfluencies are discussed relevant to these findings.

Relationships among linguistic processing speed, phonological working memory, and attention in children who stutter

Relatively recently, experimental studies of linguistic processing speed in children who stutter (CWS) have emerged, some of which suggest differences in performance among CWS compared to children who do not stutter (CWNS). What is not yet well understood is the extent to which underlying cognitive skills may impact performance on timed tasks of linguistic performance. The purpose of this study was to explore possible relationships between measures of linguistic processing speed and two aspects of cognition: phonological working memory and attention. Participants were 9 CWS and 14 CWNS between the ages of 3;6 and 5;2. Children participated in a computerized picture naming task (an index of linguistic processing speed) and a nonword repetition task (an index of phonological working memory). Parents completed a temperament behavior questionnaire, from which information about the children's attentional skills was collected. Findings revealed that the groups did not differ from each other on speed of picture naming or attention; however, the CWS performed significantly worse in nonword repetition. In addition, after partialling out the effects of age, (a) for CWS only, there was a significant negative relationship between picture naming speed and nonword repetition; (b) there were no significant relationships for either group between aspects of attention and picture naming speed; and (c) only the CWNS showed a significant relationship between nonword repetition and focused attentional skills. These results underscore the need to consider the underlying skills associated with lexically related aspects of language production when examining the task performances of CWS and CWNS.

EDUCATIONAL OBJECTIVES

The reader will be able to: (a) summarize findings from previous studies examining the speech and language performance of children who do (CWS) and do not stutter (CWNS); (b) describe findings of previous studies related to nonword repetition and attention in CWS; (c) compare the results of the present study with previous work in this area; and (d) discuss speculations concerning the relationship between linguistic processing speed, phonological working memory, and attention in CWS and CWNS.

Effects of word frequency and phonological neighborhood characteristics on confrontation naming in children who stutter and normally fluent peers

In a prior study (Newman & Bernstein Ratner, 2007), we examined the effects of word frequency and phonological neighborhood characteristics on confrontation naming latency, accuracy and fluency in adults who stutter and typically fluent speakers. A small difference in accuracy favoring fluent adults was noted, but no other patterns differentiated fluent speaker responses from those obtained from the adults who stutter. Because lexical organization or retrieval differences might be more easily observed in less mature language users, we replicated the experiment using 15 children who stutter (ages 4;10 16;2) and age- and gender-matched peers. Results replicated the earlier study: the two groups of participants showed strikingly similar patterns of responses based on word frequency and neighborhood characteristics. There were also no differences in naming accuracy overall between the two groups. Given our results and those of other researchers who have explored the impact of neighborhood variables on lexical retrieval in people who stutter, we suggest that differences between language production in PWS and fluent speakers are not likely to involve atypical phonological organization of lexical neighborhoods.

EDUCATIONAL OBJECTIVES

After reading this article, the reader will be able to: (1) define and illustrate words that have differing frequency and phonological neighborhood characteristics; (2) evaluate whether or not children who stutter appear to organize their mental lexicons differently than those of children who are typically fluent; (3) suggest future areas of research into language processing in people who stutter.

The dark side of incremental learning: a model of cumulative semantic interference during lexical access in speech production

Naming a picture of a dog primes the subsequent naming of a picture of a dog (repetition priming) and interferes with the subsequent naming of a picture of a cat (semantic interference). Behavioral studies suggest that these effects derive from persistent changes in the way that words are activated and selected for production, and some have claimed that the findings are only understandable by positing a competitive mechanism for lexical selection. We present a simple model of lexical retrieval in speech production that applies error-driven learning to its lexical activation network. This model naturally produces repetition priming and semantic interference effects. It predicts the major findings from several published experiments, demonstrating that these effects may arise from incremental learning. Furthermore, analysis of the model suggests that competition during lexical selection is not necessary for semantic interference if the learning process is itself competitive.

Sentence position and syntactic complexity of stuttering in early childhood: a longitudinal study

The purpose of the present investigation was to assess longitudinal word- and sentence-level measures of stuttering in young children. Participants included 12 stuttering and non-stuttering children between 36 and 71 months of age at an initial visit who exhibited a range of stuttering rates. Parent-child spontaneous speech samples were obtained over a period of two years at six-month intervals. Each speech sample was transcribed, and both stuttering-like disfluencies (SLDs) and other disfluencies (ODs) were coded. Word- and sentence-level measures of SLDs were used to assess linguistic characteristics of stuttering. Results of the word-level analysis indicated that stuttering was most likely to occur at the sentence-initial position, and that a tendency to stutter on function words was present only at the sentence-initial position. Results of the sentence-level analyses indicated that sentences containing ODs and those containing SLDs were both significantly longer and more complex than fluent sentences, but did not differ from each other. Word- and sentence-level measures also did not change across visits. Results were taken to suggest that both SLDs and ODs originate during the same stage of sentence planning.

EDUCATIONAL OBJECTIVES

The reader will be able to: (1) describe the importance of sentence position in the occurrence of speech disfluencies, (2) describe the relation between sentence complexity and the occurrence of speech disfluencies, and (3) describe the potential role of different aspects of sentence planning on the occurrence of speech disfluencies.