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Purpose: We evaluated whether naive listeners' ratings of the gender typicality of the speech of children assigned male at birth (AMAB) and children assigned female at birth (AFAB) were different at two time points: one at which children were 2.5-3.5 years old and one when they were 4.5-5.5 years old. We also examined whether measures of speech, language, and inhibitory control predicted developmental changes in these ratings. Method: A group of adults (N = 80) rated single-word productions of 55 AMAB and 55 AFAB children on a continuous scale from "definitely a boy" to "definitely a girl." Children's productions were taken from previous longitudinal study of phonological development and vocabulary growth. As part of that study, children completed a battery of standardized and nonstandardized tests at both time points. Results: Listener ratings for AMAB and AFAB children were significantly different at both time points. The difference was larger at the later time point, and this was due entirely to changes in the ratings of AMAB children's speech. A measure of language production and a measure of inhibitory control predicted developmental changes in these ratings, albeit only weakly, and not in a consistent direction. Conclusions: The gender typicality of AMAB and AFAB children's speech is perceptibly different for children as young as 2.5 years old. Developmental changes in perceived gender typicality are driven by changes in the speech of AMAB children. The learning of gendered speech is not constrained or facilitated by overall speech and language skill.

Purpose: We evaluated whether children whose inaccurate /[voiced alveolar approximant]/ productions showed evidence phonetic differentiation with /w/ at 3.5-4.5 years of age improved in /[voiced alveolar approximant]/ production over the next year more than children whose inaccurate productions did not show evidence of such differentiation. We also examined whether speech perception, inhibitory control, and vocabulary size predicted growth in /[voiced alveolar approximant]/. Method: A set of typically developing, monolingual English-speaking preschool children (n = 136) produced tokens of /[voiced alveolar approximant]/- and /w/-initial words at two time points (TPs), at which they were 39-52 and 51-65 months old. Children's productions of /[voiced alveolar approximant]/ and /w/ were narrowly phonetically transcribed. Children's productions at the earlier time point were rated by naïve listeners using a visual analog scale measure of phoneme goodness; these ratings were used to assess the degree of phonetic differentiation between /[voiced alveolar approximant]/ and /w/. Results: Accuracy for both phonemes varied considerably at both TPs. The growth in accuracy of /[voiced alveolar approximant]/ between the two TPs was not predicted by any individual-differences measures, nor by the degree of differentiation between /[voiced alveolar approximant]/ and /w/at the earlier time point. Conclusion: Low vocabulary size, low inhibitory control, poor speech perception, and the absence of early phonetic differentiation are not necessarily limiting factors in predicting /[voiced alveolar approximant]/ growth in individual children in the age range we studied.

Purpose: Item response theory (IRT) is a psychometric approach to measurement that uses latent trait abilities (e.g., speech sound production skills) to model performance on individual items that vary by difficulty and discrimination. An IRT analysis was applied to preschoolers' productions of the words on the Goldman-Fristoe Test of Articulation-Second Edition (GFTA-2) to identify candidates for a screening measure of speech sound production skills. Method: The phoneme accuracies from 154 preschoolers, with speech skills on the GFTA-2 ranging from the 1st to above the 90th percentile, were analyzed with a 2- parameter logistic model. Results: A total of 108 of the 232 phonemes from stimuli in the sounds-in-words subtest fit the IRT model. These phonemes, and subgroups of the most difficult of these phonemes, correlated significantly with the children's overall percentile scores on the GFTA-2. Regression equations calculated for the 5 and 10 most difficult phonemes predicted overall percentile score at levels commensurate with other screening measures. Conclusions: These results suggest that speech production accuracy can be screened effectively with a small number of sounds. They motivate further research toward the development of a screening measure of children's speech sound production skills whose stimuli consist of a limited number of difficult phonemes.

Purpose The aims of the present study are (a) to quantify the developmental sequence of fricative mastery in Putonghua-speaking children and discuss the observed pattern in relation to existing theoretical positions, and (b) to describe the acquisition of the fine-articulatory/acoustic details of fricatives in the multidimensional acoustic space. Method Twenty adults and 97 children participated in a speech-production experiment, repeating a list of fricative-initial words. Two independent measures were applied to quantify the relative sequence of fricative acquisition: auditory-based phonetic transcription and acoustics-based statistical modeling. Two acoustic parameters--fricative centroid frequency and F2 onset--were used to index tongue-body and tongue-tip development, respectively. Results Both transcription and statistical modeling of acoustics yielded the sequence of /?/ ? /?/ ? /s/. Acoustic analysis further revealed gradual separation in both acoustic dimensions, with the initial undifferentiated form ambiguous between/?/ and /?/. Conclusions The observed sound-acquisition order was interpreted as reflecting a combined influence of both oromotor maturation and language-specific phoneme frequency in Putonghua. Acoustic results suggest a maturational advantage of the tongue body over the tongue tip during fricative development.

Purpose: The authors examined the relationship between adults' perception of the accuracy of children's speech and acoustic detail in their subsequent productions to children. Method: Twenty-two adults participated in a task in which they rated the accuracy of 2- and 3-year-old children's word-initial /s/ and /[esh]/ using a visual analog scale (VAS), then produced a token of the same word as if they were responding to the child whose speech they had just rated. Result: The duration of adults' fricatives varied as a function of their perception of the accuracy of children's speech: Longer fricatives were produced following productions that they rated as inaccurate. This tendency to modify duration in response to perceived inaccurate tokens was mediated by measures of self-reported experience interacting with children. However, speakers did not increase the spectral distinctiveness of their fricatives following the perception of inaccurate tokens. Conclusion: These results suggest that adults modify temporal features of their speech in response to perceiving children's inaccurate productions. These longer fricatives are potentially both enhanced input to children and an error-corrective signal.

Research has shown that children repeat high-probability phoneme sequences more accurately than low-probability ones. This effect attenuates with age, and its decrease is predicted by developmental changes in the size of the lexicon (J. Edwards, M. E. Beckman, & B. Munson, 2004; B. Munson, 2001; B. Munson, J. Edwards, & M. Beckman, 2005). This study expands on these findings by examining relationships between vocabulary size and repetition accuracy of nonwords varying in phonotactic probability by 16 children with specific language impairment (SLI), 16 chronological-age-matched (CA) peers with typical speech and language development, and 16 younger children matched with the children with SLI on vocabulary size (VS). As in previous research, children with SLI repeated nonwords less accurately than did CA children. The children with SLI and the VS children showed similar levels of nonword repetition accuracy. Phonotactic probability affected repetition accuracy more for children with SLI and VS children than for CA children. Regression analyses showed that measures of vocabulary size were the best predictor of the difference in repetition accuracy between high- and low-probability sequences. Analyses by items showed that measures of phonotactic probability were stronger predictors of repetition accuracy than judgments of wordlikeness. Taken together, the results support research demonstrating that vocabulary size mediates the influence of phonotactic probability on nonword repetition, perhaps due to its influence on the ongoing refinement of phonological categories. (Contains 3 figures, 1 footnote, and 5 tables.)

This study examined the structure of children's mental lexicons through performance on 2 short experimental tasks, 1 in which children repeated familiar monosyllabic real words varying in neighborhood density and 1 in which they repeated CVC nonwords varying in phonotactic probability. Two groups of typically developing children with mean ages of 4;3 (years; months; n = 16) and 7;2 (n = 15) participated. In the group of younger children, offset-to-onset response latencies were not systematically affected by lexicality, phonotactic probability, or neighborhood density. Onset-to-onset latencies showed an effect of phonotactic probability on nonword repetition. Children in the older group repeated high-density real words with longer latencies than low-density real words. They also repeated high-probability nonwords with shorter latencies than low-probability nonwords. This was true for both the onset-to-onset andoffset-to-onset repetition latencies. Children in both age groups repeated vowels embedded in high-probability nonwords with shorter durations than vowels embedded in low-probability nonwords. These findings suggest that lexical competition and phonological facilitation emerge in development and that the rate of development is different for different dependent measures.KEY WORDS: phonological neighborhood density, phonotactic probability, nonword repetition, real-word repetition, children

A growing body of research has documented effects of phonotactic probability on young children's nonword repetition. This study extends this research in 2 ways. First, it compares nonword repetitions by 40 young children with phonological disorders with those by 40 same-age peers with typical phonological development on a nonword repetition task in which the frequency of embedded diphone sequences was varied. Second, it examines the relationship between the frequency effect in the nonword repetition task and other measures of linguistic ability in these children. Children in both groups repeated low-frequency sequences less accurately than high-frequency sequences. The children with phonological disorders were less accurate overall but showed no larger disadvantage for the low-frequency sequences than their age peers. Across the group, the size of the frequency effect was correlated with vocabulary size, but it was independent of measures of speech perception and articulatory ability. These results support the hypothesis that the production difficulty associated with low-frequency sequences is related primarily to vocabulary growth rather than to developments in articulatory or perceptual ability. By contrast, production problems experienced by children with phonological disorders do not appear to result from difficulties in making abstractions over known lexical items. Instead, they may be associated with difficulties in building representations in the primary sensory and motor domains.KEY WORDS: nonword repetition, phonological disorder, vocabulary size, speech perception, frequency

Recent literature suggests that phonological neighborhood density and word frequency can affect speech production, in addition to the well-documented effects that they have on speech perception. This article describes 2 experiments that examined how phonological neighborhood density influences the durations and formant frequencies of adults' productions of vowels in real words. In Experiment 1, 10 normal speakers produced words that covaried in phonological neighborhood density and word frequency. Infrequent words with many phonological neighbors were produced with shorter durations and more expanded vowel spaces than frequent words with few phonological neighbors. Results of this experiment confirmed that this effect was not related to the duration of the vowels constituting the high- and low-density words. In Experiment 2, 15 adults produced words that varied in both word frequency and neighborhood density. Neighborhood density affected vowel articulation in both high- and low-frequency words. Moreover, frequent words were produced with more contracted vowel spaces than infrequent words. There was no interaction between these factors, and the vowel duration did not vary as a function of neighborhood density. Taken together, the results suggest that neighborhood density affects vowel production independent of word frequency and vowel duration.KEY WORDS: phonological neighborhood density, word frequency, vowels, acoustic measurements, adults

Assessment of tongue strength and endurance is common in research and clinical contexts. It is unclear whether the results reveal discrete function by the tongue or combined abilities of the tongue and jaw. One way to isolate the movement of the tongue is to constrain the jaw kinematically by using a bite block. In this study, 10 neurologically normal young adults performed tongue strength and endurance tasks without a bite block ("jaw-free") and with bite blocks of various heights (2, 5, 10, and 15 mm for strength; 5 mm for endurance). Data signals included tongue pressure exerted on an air-filled bulb, surface electromyography (SEMG) from the superior tongue blade, and SEMG from 1 masseter. On average, tongue strength (pressure in kPa) was greatest with no bite block and generally decreased as bite blocks increased in height. Pairwise analyses revealed statistically significant differences for all but 3 comparisons (jaw-free to 2 mm, 2 to 5 mm, and 5 to 10 mm). After removing outlying data from 1 participant, tongue endurance at 50% of tongue strength was significantly greater without a bite block than with one. SEMG data did not differ significantly for the strength task across bite block conditions, but inspection of the individual data revealed a tendency for masseter activity to be lower when the jaw was unconstrained. These results suggest that maximar tongue strength and endurance are best assessed with an unconstrained mandible or with a very small bite block.

This study examined spoken word recognition in adults with cochlear implants (CIs) to determine the extent to which linguistic and cognitive abilities predict variability in speech-perception performance. Both a traditional consonant-vowel-consonant (CVC)-repetition measure and a gated-word recognition measure (F. Grosjean, 1996) were used. Stimuli in the gated-word-recognition task varied in neighborhood density. Adults with CIs repeated CVC words less accurately than did age-matched adults with normal hearing sensitivity (NH). In addition, adults with CIs required more acoustic information to recognize gated words than did adults with NH. Neighborhood density had a smaller influence on gated-word recognition by adults with CIs than on recognition by adults with NH. With the exception of 1 outlying participant, standardized, norm-referenced measures of cognitive and linguistic abilities were not correlated with word-recognition measures. Taken together, these results do not support the hypothesis that cognitive and linguistic abilities predict variability in speech-perception performance in a heterogeneous group of adults with CIs. Findings are discussed in light of the potential role of auditory perception in mediating relations among cognitive and linguistic skill and spoken word recognition.

Adults' performance on a variety of tasks suggests that phonological processing of nonwords is grounded in generalizations about sublexical patterns over all known words. A small body of research suggests that children's phonological acquisition is similarly based on generalizations over the lexicon. To test this account, production accuracy and fluency were examined in nonword repetitions by 104 children and 22 adults. Stimuli were 22 pairs of nonwords, in which one nonword contained a low-frequency or unattested two-phoneme sequence and the other contained a high-frequency sequence. For a subset of these nonword pairs, segment durations were measured. The same sound was produced with a longer duration (less fluently) when it appeared in a low-frequency sequence, as compared to a high-frequency sequence. Low-frequency sequences were also repeated with lower accuracy than high-frequency sequences. Moreover, children with smaller vocabularies showed a larger influence of frequency on accuracy than children with larger vocabularies. Taken together, these results provide support for a model of phonological acquisition in which knowledge of sublexical units emerges from generalizations made over lexical items.KEY WORDS: phonological development, lexical development, phonotactic probability

Previous research has found developmental decreases in temporal variability in speech. Relatively less work has examined spectral variability, and, in particular, variability in consonant spectra. This article examined variability in productions of the consonant/s/by adults and by 3 groups of children, with mean ages of 3;11 (years; months), 5;04, and 8;04. Specifically, it measured the influence of age, phonetic context, and syllabic context on variability. Spectral variability was estimated by measuring dynamic spectral characteristics of multiple productions of/s/ in sV, spV, and swV sequences, where the vowel was either/a/ or /u/. Mean duration, variability in duration, and coarticulation were also measured. Children were found to produce /s/ with greater temporal and spectral variability than adults. Duration and coarticulation were comparable across the 4 age groups. Spectral variability was greater in swV contexts than in sV or spV sequences. The lack of consistent effects of phonetic context on spectral variability suggests that the developmental differences were related to subtle variability in place of articulation for /s/ in the children's productions.

This study examined whether accuracy in producing linguistic stress reliably distinguished between five children with suspected developmental apraxia of speech (sDAS) and five children with phonological disorder (PD). No group differences in the production of stress were found; however, listeners judged that nonword repetitions of the children with sDAS were less accurate than those of children with PD. (Contains references.) (Author/DB)

Data from a study on lexical processing involving 66 children (mean age 6 years 9 months) with specific language impairments and 66 typically developing children. No significant correlations were found between response times on a series of tasks and language test scores. Results suggest that there is no linear relation between speed of processing and severity of language impairment. (Contains references.) (Author/DB)

Recent studies have suggested that both adults and children are sensitive to information about phonological pattern frequency, however, the influence of phonological pattern frequency on speech production has not been studied extensively. The current study examined the effect of phonological pattern frequency on the fluency and flexibility of speech production. Normal- and fast-rate nonsense-word repetitions of three groups of participants (preschool children, school-aged children, and adults) were analyzed. Subjective ratings of the wordlikeness of nonsense words, percentage phonemes correctly repeated, mean duration, and durational variability were measured. In the first experiment, ratings of the wordlikeness of nonsense words were found to correlate with the pattern frequency of sequences embedded in them. In the second analysis, it was found that children, but not adults, repeated infrequent sequences of phonemes less accurately than frequent sequences. In the third experiment, infrequent sequences were produced with longer durations than frequent ones, with children demonstrating a larger difference between frequent and infrequent sequences than adults. Phonological pattern frequency also influenced variability in duration: infrequent sequences of sounds were more variable than frequent ones. Thus, there appears to be an influence of phonological pattern frequency on speech, and, for some measures, a larger effect size is noted for children. KEY WORDS: Nonword repetition, frequency, speech production, children, A large literature has demonstrated that phonological processing is sensitive to lexical frequency. For example, frequent words are produced with shorter acoustic durations and are produced with fewer spontaneous speech [...]