Bilingual phonological acquisition: the influence of language-internal, language-external, and lexical factors

The Effects of Phonological Complexity on Word Production in French-Speaking Children

Word complexity indices, such as the Index of Phonetic Complexity (IPC) and the Word Complexity Measure (WCM), code a word in terms of featural and structural properties that pose difficulty in phonological development. Studies have investigated the influence of complexity indices on vocabulary development; however, few have examined their influence on consonant accuracy. Furthermore, these indices were developed for English-speaking children and have not been widely applied to other languages. This study investigates whether a word's phonological complexity influences how accurately it is produced in French-speaking children. Four databases consisting of the productions of children (n = 74), aged 1;11 to 4;9, were analyzed. Words were coded in terms of the IPC, WCM, and parameters that add complexity during phonological development. Using mixed-effects logistic regression, we examined whether phonological complexity as determined by the IPC, WCM, or by alternative indices better accounts for the influence of complexity on production. We also investigated whether the accuracy of a target sound/structure was influenced by a word's complexity. Results indicated that complexity based on the IPC or WCM significantly influenced consonant accuracy; however, indices tapping fewer features provided superior model fit. At younger ages, the presence of fricatives/liquids and, at all ages, the presence of alveopalatal fricatives, codas, and clusters significantly influenced accuracy. Findings were inconclusive as to whether whole word complexity influenced the accuracy of a target sound/structure. Results suggest that current complexity indices provide only approximate indications of how featural and structural properties of words influence production.

Sources of individual differences in the dual language development of heritage bilinguals

Bilingual children are a more heterogenous group than their monolingual counterparts with respect to the sources of variation in their language learning environments, as well as the wide individual variation in their language abilities. Such heterogeneity in both individual difference factors and language abilities argues for the importance of an individual differences approach in research on bilingual development. The main objective of this article is to provide a review and synthesis of research on the sources of individual differences in the second language (L2) and heritage language (HL) development of child bilinguals. Several child-internal and child-external individual difference factors are discussed with respect to their influence on children's dual language abilities. In addition, the emergent research on individual differences in bilingual children with developmental language disorder is reviewed. Both the theoretical and applied relevance of individual difference approaches to bilingual development are discussed.

Exploring word production in three-year-old monolingual French-speaking children

There is a general need for more knowledge on the development of French phonology, and little information is currently available for typically developing French-speaking three-year-old children. This study took place in Belgium and explores the accuracy of speech production of 34 typically developing French-speaking children using a picture naming task. Measures of speech accuracy revealed lower performance than previously seen in the literature. We investigated speech accuracy across different phonological contexts in light of characteristics of target words that are known to have an influence on speech production, namely the condition of production (spontaneous vs. imitated), the length of the word (in number of syllables), syllable complexity (singleton vs. cluster) and positional complexity (onset vs. coda). Results indicate that the accuracy of words produced spontaneously did not differ from imitated words. The presence of consonant clusters in the target word was associated with lower performance on measures of Percentage of Consonants Correct and Whole Word Proximity for both 1- and 4-syllable words. Singleton codas were produced less accurately than onsets in 1-syllable words. Word-internal singleton codas were produced less accurately than final codas. In our sample, 1-syllable words showed surprisingly low levels of performance which we can explain by an over-representation of phonologically complex properties in the target words used in the present study. These results highlight the importance of assessing various aspects of phonological complexity in French speech tasks in order to detect developmental errors in typically developing children and, ultimately, help identify children with speech sound disorders.

Complexity and cross-linguistic transfer in intervention for Spanish–English bilingual children with speech sound disorder

With bilingual children, intervention for speech sound disorders must consider both of the child’s phonological systems, which are known to interact with each other in development. Further, cross-linguistic generalization following intervention for bilingual children with speech sound disorders (i.e. the impact of treatment in one language on the other) has been documented to varying degrees in some prior studies. However, none to date have documented the cross-linguistic impact of treatment with complex targets (e.g. consonant clusters) for bilingual children. Because complex phonological targets have been shown to induce system-wide generalization within a single language, the potential for bilingual children to generalize learning across languages could impact the efficiency of intervention in this population. This pilot intervention study examines the system-wide, cross-linguistic effects of treatment targeting consonant clusters in Spanish for two Spanish–English bilingual children with phonological disorder. Treatment was provided with 40-minute sessions in Spanish via teletherapy, three times per week for six weeks. Comprehensive phonological probes were administered in English and Spanish prior to intervention and across multiple baselines. Pre-intervention data were compared to data from probes administered during and after intervention to generate qualitative and quantitative measures of treatment outcomes and cross-linguistic generalization. Results indicate a medium effect size for system-wide generalization in Spanish (the language of treatment) and English (not targeted in treatment), for both participants (mean effect size in Spanish: 3.6; English 4.3). These findings have implications for across-language transfer and system-wide generalization in treatment for bilingual children. 

The Development of Alveolar and Alveopalatal Fricatives in French-Speaking Monolingual and Bilingual Children

PURPOSE

This study conducted a transcription-based and spectral moments' analysis of alveolar and alveopalatal fricatives in monolingual and bilingual French-speaking children, aged 2;6-6;10 (years;months). We measured the percent accuracy of fricatives and investigated whether young children could distinguish alveolar and alveopalatal fricatives on the basis of spectral moments. In addition, we examined which child- (i.e., age, gender, bilingualism, and alveopalatal fricative inventory size) and word/sound-related (i.e., place-of-articulation [PoA], voicing, vowel quality, and word position) factors influenced spectral moments and fricative duration.

METHOD

Children (N = 89) participated in a picture-naming task in which they produced words containing alveolar /s, z/ and alveopalatal /ʃ, ʒ/ fricatives in word-initial, -medial, and -final positions. The words were transcribed and analyzed acoustically, and the first and third spectral moments (i.e., centroid and skewness) and the duration of fricatives were calculated. The data were subject to mixed-effects linear regression.

RESULTS

Percent accuracy results indicated effects of age on alveopalatal fricatives and effects of word position on voiced fricatives. Statistical models indicated that age, gender, and alveopalatal fricative inventory size influenced spectral moments. Age and inventory size interacted significantly with PoA. Children as young as age 2;6 distinguished alveopalatal and alveolar fricatives on the basis of centroid but not skewness values. The distinction between the two sets of fricatives increased with age. Bilingual children who spoke languages with greater numbers of alveopalatal fricatives distinguished alveopalatal and alveolar fricatives less well than monolinguals and bilinguals who spoke languages with fewer numbers of alveopalatal fricatives. Girls had higher centroid and lower skewness values than boys. Models also revealed a significant influence of word/sound-related factors (voicing, vowel quality, and word position) on spectral moments and fricative duration.

CONCLUSIONS

Findings indicated that multiple factors influence the spectral moments and duration measures of children's alveolar and alveopalatal fricatives. In particular, we found that spectral moments were sensitive to gender and bilingualism effects.

Internal and external factors contributing to variability in consonant accuracy of Arabic-French simultaneous bilingual children

This study aims to describe the relationships between child-internal and child-external factors and the consonant accuracy of bilingual children. More specifically, the study looks at internal factors: expressive and receptive vocabulary, and external factors: language exposure and language status, of a group of 4-year-old bilingual Arabic-French children. We measured the consonant accuracy of the children by the percentage of correct consonants in a Picture-Naming Task and a Non-Word Repetition Task in each language. The results suggest a significant relationship between vocabulary and consonant accuracy. A cross-language correlation was observed between the expressive vocabulary level of the majority language (French) and the consonant accuracy of the minority language (Arabic). Also, a significant correlation was found between Arabic language exposure and Arabic consonant accuracy. Finally, consonant accuracy was significantly higher in French tasks than in Arabic, despite the individual differences of the children.

The Prosody of Two-Syllable Words in French-Speaking Monolingual and Bilingual Children: A Focus on Initial Accent and Final Accent

This study examined the acoustic characteristics of disyllabic words produced by French-speaking monolingual and bilingual children, aged 2;6 to 6;10, and by adults. Specifically, it investigated the influence of age, bilingualism, and vocabulary on final-to-initial syllable duration ratios and on the presence of initial and final accent. Children and adults took part in a word-naming task in which they produced a controlled set of disyllabic words. Duration and maximum pitch were measured for each syllable of the disyllabic word and these values were inserted into mixed-effects statistical models. Results indicated that children as young as 2;6 obtained final-to-initial syllable duration ratios similar to those of adults. Young children realized accent on the initial syllable more often and accent on the final syllable less often than older children and adults. There was no influence of bilingualism on the duration and pitch characteristics of disyllabic words. Children aged 2;6 with smaller vocabularies produced initial accent more often than children with large vocabularies. Our findings suggest that early word productions are constrained by developmental tendencies favouring falling pitch across an utterance.

Within- and Cross-Language Relations Between Phonological Memory, Vocabulary, and Grammar in Bilingual Children

PURPOSE

This study investigated within-language and between-language associations between phonological memory, vocabulary, and grammar in French-English (n = 43) and Spanish-English (n = 25) bilingual children at 30, 36, and 48 months. It was predicted that phonological memory would display both within-language and between-language relations to language development and that these relations would be stronger at the youngest age.

METHOD

Bilingual children participated in free-play sessions in both of their languages at each age, from which vocabulary and grammatical information (number of different words and mean length of utterance) was extracted. Vocabulary information was also obtained from parent inventories completed when the children were 30 months and a standardized receptive vocabulary test administered at 36 and 48 months. The children were also administered nonword repetition tests in both of their languages at each age.

RESULTS

Mixed logistic regression indicated that phonological memory was associated with vocabulary and grammar within the same language and phonological memory in the other language. In two of the four statistical models, phonological memory exhibited positive between-language relations, and in one model, it exhibited negative between-language relations to language development. Results also indicated that within-language and between-languages effects remained constant, or between-language associations decreased during the age range studied.

CONCLUSION

Overall, the findings provide some support for cross-language associations between phonological memory and lexical and grammatical skills.

Relations between phonological production, grammar and the lexicon in bilingual French-English children

AIMS AND OBJECTIVES

This study examines multiple associations between language domains in bilingual children with a focus on phonology. Previous studies indicate within- but not cross-language associations between vocabulary and grammar in bilingual children. We investigate whether the relation between phonology and other language domains differs from the one reported between vocabulary and grammar.

METHODOLOGY

Canadian French-English bilingual children (n = 31), aged 31 months, participated in 2 free-play sessions, from which lexical, grammatical and phonological information was extracted. The children's parents completed the MacArthur-Bates Communicative Developmental Inventories and its Canadian French adaptation providing additional information on vocabulary and grammar in each of the children's languages. They also completed a questionnaire on their children's exposure to French and English.

DATA ANALYSIS

Within and cross-language relations between phonology, vocabulary and grammar were investigated using correlational analyses and mixed logistic regression.

FINDINGS

Correlational analyses did not reveal significant cross-language relations between phonology, vocabulary and grammar. However, mixed logistic regression, which controlled for language exposure effects, indicated that phonology was influenced by vocabulary and grammar both within and across languages.

ORIGINALITY

This study is one of the first to study cross-domain relations involving phonology in young bilingual children.

IMPLICATIONS

Overall, the findings suggest that phonology displays a pattern of relations that is different from other language domains engendering between-language effects due to a language-general component.

Variation in quality of maternal input and development of coda stops in English-speaking children in Singapore

This study examines the effects of input quality on early phonological acquisition by investigating whether interadult variation in specific phonetic properties in the input is reflected in the production of their children. We analysed the English coda stop release patterns in the spontaneous speech of fourteen mothers and compared them with the spontaneous production of their preschool children. The analysis revealed a very strong positive input-production relationship; mothers who released coda stops to a lesser degree also had children who tended to not release their stops, and the same was true for mothers who released their stops to a higher degree. The findings suggest that young children are sensitive to acoustic properties that are subphonemic, and these properties are also reflected in their production, showing the importance of considering input quality when investigating child production.

Intraword Variability in French-Speaking Monolingual and Bilingual Children

Purpose This study examines intraword variability in 40 typically developing French-speaking monolingual and bilingual children, aged 2;6-4;8 (years;months). Specifically, it measures rate of intraword variability and investigates which factors best account for it. They include child-specific ones such as age, expressive vocabulary, gender, bilingual status, and speech sound production ability, and word-specific factors, such as phonological complexity (including number of syllables), phonological neighborhood density (PND), and word frequency. Method A variability test was developed, consisting of 25 words, which differed in terms of phonological complexity, PND, and word frequency. Children produced three exemplars of each word during a single session, and productions of words were coded as variable or not variable. In addition, children were administered an expressive vocabulary test and two tests tapping speech motor ability (oral motor assessment and diadochokinetic test). Speech sound ability was also assessed by measuring percent consonants correct on all words produced by the children during the session. Data were entered into a binomial logistic regression. Results Average intraword variability was 29% across all children. Several factors were found to predict intraword variability including age, gender, bilingual status, speech sound production ability, phonological complexity, and PND. Conclusions Intraword variability was found to be lower in French than what has been reported in English, consistent with phonological differences between French and English. Our findings support those of other investigators in indicating that the factors influencing intraword variability are multiple and reflect sources at various levels in the speech processing system.

Coda consonant production in French-speaking children

This study examined coda production in French-speaking children, aged 2;6 to 6;10 (n = 141). The primary aim was to provide normative information on coda production with a large group of children. The secondary aim was to investigate factors which influence coda production such as age, manner and place of articulation, word length, word position, and bilingualism. Children took part in a word-naming task in which they produced words containing word-final and -medial codas. Results indicated that French-speaking children, as young as 2;6, produce word-final codas with a high degree of accuracy (i.e. 80%). Age had minimal effects on coda presence (i.e., whether a coda was realized or not) but it did influence coda accuracy (i.e. whether a coda was realized target-like). Older children had better coda accuracy scores than younger children. Manner of articulation influenced coda production: the younger children had the lowest scores for liquid and fricative codas whereas the older children, for fricative codas. A closer examination of coda production according to voicing revealed it was voiced obstruent codas which obtained low accuracy scores across age groups. Word-length influenced coda realization with the youngest age group producing codas more often in one- versus two-syllable words. Children produced codas more often in word-final versus word-medial position with the greatest differences evident in the youngest children. Bilinguals obtained better coda scores than monolinguals at the youngest ages and poorer ones at the oldest ages. The study concludes with a discussion of the clinical implications of the findings.

Correlation between the measure for cluster proximity (MCP) and the percentage of consonants correct (PCC)

A measure was recently proposed for the quantitative evaluation of consonant clusters in child developmental speech, the measure for cluster proximity (MCP). Its advantage over the widely used measure of the percentage of consonants correct (PCC) is that it differentiates the three main stages of cluster production: reduction, vowel epenthesis, and two-members, correct or not. The purpose of the present article is two-fold: a) to contrast MCP and PCC in two-member word-initial clusters produced within children with speech sound disorders (SSDs), tested before and after therapy, as well as in running speech within typically developing children, and b) to examine the correlation between the two measures across children in typical or atypical speech development. Data used are comprised of 34 sets with 18 word-initial cluster types, taken from the speech samples of 18 children. It is found that while there are generally large deviations between the two measures in individual clusters within and between children, the measures have a strong and statistically significant correlation when averaged over all clusters per child, or over all children per cluster class based on the manner of articulation. For the data at hand, a linear equation is obtained yielding MCP values from PCC values with a high coefficient of determination. The results suggest that PCC norms that are used to assess consonants can be used to predict MCP norms in order to assess consonant clusters in child developmental speech.

What factors influence phonological production in French-speaking bilingual children, aged three to six years?

This study examines the influence of bilingual status, language-internal (complexity of L1 phonology), language-external (dominance), and lexical (L2 vocabulary score) factors on phonological production in French-speaking monolingual (n = 37) and bilingual children (n = 64) aged three to six years. Children participated in an object and picture naming task which tested different phonological features. The bilinguals' first languages were coded in terms of the complexity of these phonological features. In addition, the parents completed a questionnaire on their child's language dominance and the children were administered a vocabulary test in their L2. Results indicated that vocabulary was the principal predictor of phonological accuracy across both age groups. Apparent monolingual-bilingual differences and dominance effects could largely be explained by vocabulary scores: children who scored better on a vocabulary test obtained superior phonological accuracy. Language-internal effects were minimal and marginally influenced vowel accuracy only.

Arabic-Spanish Language Contact in Puerto Rico: A Case of Glottal Stop Epenthesis

The current study examines the realization of adjacent vowels across word boundaries in Arabic-Spanish bilinguals and Spanish monolinguals in Puerto Rico, focusing specifically on the rate of glottal stop epenthesis in this context (e.g., hombre africano to [ˈom.bre.ʔa.fri.ˈka.no]). It was hypothesized that Arabic-Spanish bilinguals would show a higher rate of glottal stop epenthesis than Spanish monolinguals because of transfer from Arabic. In addition, we investigated the possible effects of stress, vowel height, language dominance and bilingual type on the rate of glottal stop epenthesis. Results from a reading task with 8 participants showed no significant difference in glottalization between bilinguals and monolinguals. For monolinguals, glottalization was significantly more likely when the first vowel was low or stressed; significant interactions between vowel height and stress were found for the bilingual group. Language dominance was a significant factor, with Arabic-dominant bilinguals glottalizing more than the Spanish-dominant bilinguals. In addition, early sequential bilinguals favored glottalization slightly more than simultaneous bilinguals, without reaching significance. Our data suggests some effects of syllable structure transfer from Arabic, particularly in Arabic-dominant participants. To our knowledge, our study is the first exploration of Arabic and Spanish in contact in Puerto Rico, and the first to acoustically examine the speech of Arabic-Spanish bilinguals.