Normal Phonological Development Research Articles

Classifying disordered speech

In this account we address phonological processes, and in particular, stridency deletion. We discuss the difference between stridency and sibilance, and then outline the variety of patterns that are claimed to make up the process. We look in turn at patterns of normal phonological development of fricatives in English, and typical patterns found in phonological disorders, and note that these do not provide evidence to support using the concept of stridency. Further, evidence is provided from the phonetic level in both normal acquisition and articulatory disorders that supports a sibilant versus non-sibilant analysis, and we consider why sibilant fricatives should provide especial challenges to speakers. We conclude by considering two problems. The first is a problem with imprecise phonetic description suggesting that a phonological substitution of target alveolar fricatives by dental ones occurs much more often that it really does. The second is the problem of ad hoc process invention by speech-language pathology researchers beyond the limits described in the original theory of natural phonology. We hope to have shown, therefore, that not only is stridency deletion not a process, but stridency is not a helpful concept in clinical phonology, and processes are currently used simply as convenient labels with little theoretical validity.

The rhaeadr effect in clinical phonology

A distinction is drawn between Crystal’s bucket theory of language processing and an overflow of effects between different linguistic levels in language production. Most of the examples are drawn from Welsh (a language of mutual interest to the author and the honoree of this issue). For that reason, it is proposed that this effect is termed the rhaeadr effect (from the Welsh for waterfall). The rhaeadr effect is illustrated with the initial consonant mutation systems of Welsh and Irish, and with data from both normal phonological (and morphophonological) development and disordered speech.

O desenvolvimento da consciência fonoarticulatória e a relação entre a percepção e a produção do gesto fonoarticulatório

To investigate the articulatory awareness of children with normal phonological development according to the variables gender, age and schooling, as well as to analyze their performances in speech perception and production tasks. Participants were 90 Preschool and Elementary School students, with ages between 5 and 7 years, who were evaluated using the Articulatory Awareness Investigation Instrument (AAII). The test is subdivided into three articulatory gesture perception tasks (T1, T3 and T4) and two articulatory gesture production tasks (T2 and T5). Girls showed better performances in T1, T2, T3, total score, and articulatory awareness perception tasks. Seven-year-old subjects presented better performances in T1, T4, T5, total score, articulatory awareness perception and production tasks, when compared to 5-year-olds. Seven-year-old children presented better performances than 6-year-olds in T4. Six-year-old subjects showed better performances than 5-year-olds in T5, total score, and articulatory awareness production tasks. Elementary school students presented better performances than Preschool children in T1, T3, T4, T5, total score, and articulatory awareness perception and production tasks. There was correlation between articulatory awareness perception and production tasks, evidencing that the better the performance on perception tasks, the better the performance on the production tasks. Articulatory awareness improves with age and schooling. Female subjects show better performances than male subjects. The better the performance on articulatory awareness perception tasks, the better the performance on articulatory awareness production tasks.

Random gap detection test and random gap detection test-expanded: Results in children with previous language delay in early childhood

Objectives The children with difficulty in receiving sounds presented at rapid rates in speech sounds and language learning period, may have delay in speech sounds and language development due to hearing speech sounds not clearly. Auditory temporal processing (ATP) is the ability to perceive auditory signals of brief duration accurately when presented at rapid rates. ATP can be evaluated by the random gap detection test (RGDT), which detects a brief gap between two stimuli. In this study, we investigated performance of children with previous language delay (PLD), currently having disorders in more than one speech sounds, on random gap detection test (RGDT) and RGDT-expanded (RGDT-EXP) tests. Methods 12 children (8 male, 4 female) with previous language delay (PLD) and complaint of expressing speech sounds distorted, were included into the study. They had applied language training for at least one-year period in the past and in the current time, their language development is normal. They expressed one or more speech sounds as distorted. The control group consisted of 10 normal hearing children with normal phonological development and language matched for age; and who had not PLD (5 male, 5 female). Children language levels were evaluated by Preschool Language Scale-4 test; or Clinical evaluation of language fundamentals, fourth edition (CELF-4) according to child's age. Speech sounds development was assessed by Speech Sound Development Test (SSDT). They were applied RGDT and/if necessary, RGDT-EXP. Each child responded whether he/she heard one or two tones. Their responses were taken as verbally and/or hold up one finger or two fingers. In the second test, they were applied speech discrimination test in quiet environment and in noise. Gap detection thresholds (GDTs) were detected at 500–4000 Hz; and Composite GDTs (CGDTs) were found for the study and control groups. GDT/CGDT > 20 ms was considered as abnormal for temporal processing disorder. Results In the study group with PLD, mean of the GDTs were all over the normal limits; and in control group, mean of GDTs were all in normal limits. The difference between the mean GDTs of the study group were significantly higher than the control groups at all frequencies of 500–4000 Hz. In PLD group, CGDT (103.53 ± 11.63 ms) was significantly higher than that of the control group, (10.35 ± 0.65 ms) ( p = 0.021). Conclusion The children with PLD have difficulties in perception of speech sounds at a certain rate, even they have not language learning difficulties. Therefore, difficulty in distinguishing of speech sounds may cause especially receptive language development delay. We believe that perception of the speech sounds and language in a certain speed; and temporally degraded speech programmes should be incorporated into the training programme and may help to prevent delays.

Vocabulário expressivo de crianças com desenvolvimento fonológico normal e desviante

expressive vocabulary of children with normal and deviant phonological development. to determine whether alterations presented by children with phonological disorders occur only at the phonological level or if there are any impacts on lexical acquisition; to compare the vocabulary performance of children with phonological disorders to reference values presented by the used test. participants of the study were 36 children of both genders, 14 with phonological disorders (Study group) and 22 with typical language development (Control Group). The ABFW - Vocabulary Test (Befi-Lopes, 2000) was used for assessing the expressive vocabulary of children and later to compare the performance of both groups. the performance of children with phonological disorder in the expressive vocabulary test is similar to that of children with normal phonological development. Most of the children of both groups reached the benchmarks proposed by the test for the different semantic fields. The semantic field Places demonstrated to be the most complex for both groups. the alterations presented by children with phonological disorder area limited to the phonological level, having no impact on the lexical aspect of language.

O papel das variáveis extralinguísticas idade e sexo no desenvolvimento da coda silábica

OBJETIVO: Investigar a influência dos fatores extralinguísticos no processo de aquisição dos segmentos pós-vocálicos /N, L, S, R/. MÉTODOS: A pesquisa contou com 3026 itens lexicais, provenientes dos bancos de dados AQUIFONO e INIFONO de 170 sujeitos, entre 1:2 a 3:10, com desenvolvimento fonológico normal, monolíngues, falantes do Português Brasileiro. Foi investigado o papel dos fatores linguísticos e extralinguísticos na aquisição da coda silábica, porém, foram explorados apenas os resultados das variáveis idade e sexo. A análise estatística foi realizada através do pacote VARBRUL. RESULTADOS: Ambos os fatores extralinguísticos foram relevantes no processo de aquisição fonológica normal. A idade mostrou papel estatisticamente favorável no processo de domínio de todos os fonemas nas duas posições da coda. Com o avanço da idade, ocorreu um aumento na produção correta dos fonemas, no entanto esse crescimento não foi linear. Aos 1:2 ocorreram as primeiras produções da rima VC, com o /L/ em coda final, enquanto o domínio completo dos quatro segmentos licenciados na posição de coda foi atingido em estágios que se estendem até os 3:8. Dentre as variáveis consideradas, a variável sexo foi a segunda mais selecionada pelo programa estatístico, demonstrando diferenças estatisticamente significantes para o sexo na aquisição das codas medial com /N/, /L/ e /S/ e na coda final com /L/. CONCLUSÃO: Verificou-se uma maior probabilidade de uso correto da coda com o aumento da idade, mas com a presença de regressões de uso, o que deve ser visto como uma fase normal no desenvolvimento. Quanto ao sexo, observou-se uma tendência de os meninos apresentarem maior precisão fonológica, porém isso não implica em estágios de aquisição distintos das meninas.

Segmento tardio do desempenho em linguagem de crianças com desvio fonológico após terapia fonológica

OBJETIVO: Realizar um acompanhamento tardio do desempenho em habilidades de linguagem de um grupo de estudo com histórico de desvio fonológico (após ter realizado terapia fonológica), comparando-o com um grupo controle. MÉTODOS: Dezoito sujeitos, nove do grupo de estudo e nove do controle, participaram do estudo e foram avaliados quanto à linguagem escrita a partir da aplicação de atividades de compreensão de texto, complementação de sentenças, formação de sentenças, sequencialização de parágrafos e combinação de sentenças que fazem parte do Exame de Linguagem TIPITI. RESULTADOS: Os resultados da pesquisa mostraram correlações estatísticas significantes, positivas e fortes, nas habilidades de linguagem, entre os grupos estudados e, também, diferenças estatisticamente significantes entre o grupo experimental e o grupo controle, na análise do teste Kruskal-Wallis. CONCLUSÃO: Verificou-se que, mesmo após a realização de terapia fonológica e a superação dos desvios, o grupo de estudo apresentou desempenho inferior ao do grupo controle.

Representations involved in short-term versus long-term word learning by preschool children with and without phonological disorders

This study explores whether sublexical (i.e., individual sound) and/or lexical (i.e., whole-word) representations contribute to word learning and whether these contributions change across short-term versus long-term learning. Sublexical representations were indexed by phonotactic probability, the likelihood of occurrence of a sound sequence, whereas lexical representations were indexed by neighborhood density, the number of similar sounding words. Thirty-four preschool children participated in a short-term word learning task that exposed them to nonwords varying in phonotactic probability and neighborhood density and tested learning of these nonwords. Long-term learning was assessed through comprehension and production of real words varying in phonotactic probability and neighborhood density. Results showed that phonotactic probability and neighborhood density equally influenced short-term word learning. In contrast, long-term word learning was affected primarily by neighborhood density. Thus, both sublexical and lexical representations appeared to play a role in short-term learning, but only lexical representations played a primary role in long-term retention. This pattern held for both children with normal phonological development and children with phonological delays. However, the direction of the effect of neighborhood density for short-term word learning varied by group status, suggesting differences in the use of lexical representations during short-term learning. [Work supported by NIH.]

Consonant production patterns of young severely language-delayed children with autism

While much attention has been given to documenting the language skills of verbal children with autism, the basic speech sound development patterns of severely language-impaired children with autism are unknown. Previous research has shown that certain consonants are generally produced earlier in development than other consonants, both in typically developing children and in children with language-learning impairments. While several large studies indicate that children with autism who have strong verbal skills have intact phonological development, there is some evidence that children with autism who are more severely language impaired may have abnormal phonological production. This study documents the speech sound development of non-verbal and minimally verbal children with autism. Prompts were administered for each individual speech sound while spontaneous and imitated sounds were recorded and scored. Results indicate that children with autism show the same general speech sound production patterns as typically developing and language-learning impaired children. Learning outcomes: Individuals who read this manuscript will obtain information regarding: (1) normal phonological development, (2) a comparison of speech sound production of a group of 14 children with a diagnosis of autism spectrum disorder with the production of a group of 10 typically developing children, and (3) comparisons of imitated and spontaneous sound production of the children diagnosed with autism spectrum disorder.

Phonological acquisition in Welsh – English bilingual children

Adequate assessment, diagnosis and treatment of phonological disorders require information on normal phonological development. While such data exist for many languages, they often do not exist for minority languages such as Welsh. An added factor is that speakers of such languages are often bilingual so, in the case of Welsh, it is necessary to examine norms in bilingual acquisition of Welsh and English. This article reports such a study and provides benchmarks for use by speech-language therapists in the assessment of phonological disorders in Welsh – English bilingual children. Eighty-three children from south-east Wales took part in the study. They were divided into five 6-month age groups (from 2;6 to 5;0), and into two language dominance groups (Welsh and English). There were 42 male subjects and 41 females. Data were collected via two word-lists and from spontaneous speech. The results present the ages at which the consonant systems of the two languages are acquired, and statistical analysis examine...

Patterns of phonological disability in Cantonese-speaking children in Hong Kong.

Tone, vowel and consonant production are described for a large group of Cantonese-speaking children assessed in speech and language therapy clinics in Hong Kong. The patterns of disability follow predictions made on the basis of work on normal phonological development in Cantonese, and on psychoacoustic factors in acquisition: consonants account for more disability than vowels, and tones are least problematic. Possible articulatory and auditory contributions to explanation of the observed patterns are discussed.

Phonological development in Down syndrome

This article provides an overview of the literature on phonological development in infants and children with Down syndrome. The review is divided into four major sections: the first summarizes studies of factors that may impede normal phonological development in this population: hearing loss and abnormalities of the middle ear; anatomical and physiological features of the speech mechanism; characteristics of input; and perceptual and encoding abilities. The second section examines prelinguistic vocal development and the links between babble and speech. The third section reviews literature on phonological acquisition after the onset of meaningful speech and briefly summarizes research on speech intelligibility in Down syndrome individuals. The fourth section discusses recommendations for intervention programs aimed at improving articulation and phonology in children with Down syndrome. MRDD Research Reviews 1997;3:300–306. © 1997 Wiley-Liss, Inc.

Consonant-vowel interactions in early phonological development

Existing data suggest that consonant and vowel acquisition do not occur independently in young children, but instead interact during a period of normal phonological development. The purpose of this study was to assess consonant-vowel (CV) interactions in meaningful words, in particular to determine if labials were associated with central vowels, alveolars with front vowels, and velars with back vowels. A total of nine normally-developing children provided cross-sectional and longitudinal data for 18-, 21-, and 24-month age groups. Vowel inventories and frequencies of front, central, and back vowels following different consonantal places of articulation, without regard to accuracy, are reported. Accuracies as compared with the adult target and the frequency with which front, central, and back vowels were achieved within category in each consonantal context are also reported. Results did not provide support for a bilabial-central vowel association or for an alveolar-front vowel association. There was some evidence of an association between velars and back vowels. It is suggested that CV interactions may hold for only the earliest period of lexical acquisition and with differing strengths in individual phonological systems.

A phonologically based analysis of misspellings by third graders with disordered-phonology histories.

Misspellings evidenced in written responses of third graders during administration of a battery containing 25 true words and 20 nonsense syllable items were analyzed phonologically. Children with histories of disordered phonologies evidenced more phonologically based deviations in their written misspellings than did their peers who had experienced normal phonological development. In addition, the children with disordered-phonology histories relied more on less productive spelling strategies and evidenced poorer phonological awareness skills than their peers with normal-phonology histories.

Perception and awareness of phonemes in phonologically impaired children.

Fourteen phonologically impaired children and 14 normally speaking controls were given tests of speech discrimination, in which they had to distinguish between similar phonemes, and tasks of rhyme judgement and matching words on the basis of their initial phoneme, which require the child to identify the same sounds across differing word contexts. Compared to the control group, children with phonological impairment were poor on the phoneme discrimination tasks, but there was wide variation in performance and seven of these children scored near ceiling levels. All children showed some ability to discriminate contrasts they could not produce. Substantial deficits were found in the ability of phonologically impaired children to identify phoneme constancy across differing word contexts. It is difficult to explain such findings in terms of impaired auditory discrimination. Results are discussed in relation to normal phonological development, and it is suggested that phonologically impaired children do not progress to the stage of analysing words at the level of the phoneme.

Developmental phonological disorders and normal speech development: a review and illustration

This review discusses the characteristics of phonological development from the preverbal stage of vocalizations through to the mastery of adult-like pronunciation patterns. Developmental phonological dis orders are then considered in the context of normal phonological development. Two children with unusual pronunciation patterns illus trate the characteristics of developmental phonological disorders.

A Treatment Program for Disordered Phonology

A therapy program for disordered phonology was developed by identifying unique characteristics of a child's phonological patterns and by using recent literature in normal phonological development. The goal was consistent, automatic production of word-final [z] in conversational speech. The program was designed for a 4 year 11-month-old boy who had been enrolled in articulation therapy for two years. He had several consistent errors in single words but a significantly greater number of less consistent errors in conversational speech, which made him unintelligible. The therapy program controlled the phonetic contexts for [z] production, as utterances increased in length and became less structured. The child was successful in completing the program but only moderate improvement was made between pre- and post-therapy speech sampling. Analysis of the samples revealed that the errors were not related to phonetic context. However, the child omitted [z] in certain lexical items. The results suggest that the child's errors involved more than the ability to produce [z] in a variety of phonetic contexts. Other components of the linguistic system (syntax and semantics) appear to have interacted with the phonological component, resulting in difficulty in producing [z] in certain lexical items. The interface between the various linguistic components is discussed in terms of assessing phonological abilities and planning remediation programs.