In two visual world experiments we disentangled the influence of order of mention (first vs. second mention), grammatical role (subject vs object), and semantic role (proto-agent vs proto-patient) on 7- to 10-year-olds’ real-time interpretation of German pronouns. Children listened to SVO or OVS sentences containing active accusative verbs (küssen “to kiss”) in Experiment 1 (N = 72), or dative object-experiencer verbs (gefallen “to like”) in Experiment 2 (N = 64). This was followed by the personal pronoun er or the demonstrative pronoun der. Interpretive preferences for er were most robust when high prominence cues (first mention, subject, proto-agent) were aligned onto the same entity; and the same applied to der for low prominence cues (second mention, object, proto-patient). These preferences were reduced in conditions where cues were misaligned, and there was evidence that each cue independently influenced performance. Crucially, individual variation in age predicted adult-like weighting preferences for semantic cues (Schumacher, Roberts & Järvikivi, 2017).

We test the comprehension of transitive sentences in very young learners of Mandarin Chinese using a combination of the weird word order paradigm with the use of pseudo-verbs and the preferential looking paradigm, replicating the experiment of Franck et al. (2013) on French. Seventeen typically-developing Mandarin infants (mean age: 17.4 months) participated and the same experiment was conducted with eighteen adults. The results show that hearing well-formed NP-V-NP sentences triggered infants to fixate more on a transitive scene than on a reflexive scene. In contrast, when they heard deviant NP-NP-V sequences, no such preference pattern was found, a performance pattern that is adult-like. This is at variance with some of the results from Candan et al. (2012), who only found evidence for canonical word order comprehension at almost age 3 when considering fixation time. Furthermore, within the age range tested, performance showed no effect of age or vocabulary size.

This article presents data on lexical development of 881 Israeli Hebrew-speaking monolingual toddlers ages 1;0 to 2;0. A Web-based version of the Hebrew MacArthur-Bates Communicative Development Inventories (H-MB-CDI) was used for data collection. Growth curves for expressive vocabulary, receptive vocabulary, actions and gestures were characterized. Developmental trajectories of toddlers with various demographic characteristics, such as education, income, religiosity level, birth order of the child, and child-care arrangements were compared. Results show that the lexical growth curves for Hebrew are comparable to those reported for other languages. Sex, birth order, and child-care arrangements were found to influence the size of lexicons. It is recommended that the trajectories presented here be used as norms for lexical growth among typical Hebrew-speaking toddlers in the second year of life.

Code-switching is a common phenomenon in bilingual communities, but little is known about bilingual parents’ code-switching when speaking to their infants. In a pre-registered study, we identified instances of code-switching in day-long at-home audio recordings of 21 French–English bilingual families in Montreal, Canada, who provided recordings when their infant was 10 and 18 months old. Overall, rates of infant-directed code-switching were low, averaging 7 times per hour (6 times per 1,000 words) at 10 months and increasing to 28 times per hour (18 times per 1,000 words) at 18 months. Parents code-switched more between sentences than within a sentence; this pattern was even more pronounced when infants were 18 months than when they were 10 months. The most common apparent reasons for code-switching were to bolster their infant's understanding and to teach vocabulary words. Combined, these results suggest that bilingual parents code-switch in ways that support successful bilingual language acquisition.

The current study explores variation in phonemic representation among Spanish–English dual language learners (DLLs, n = 60) who were dominant in English or in Spanish. Children were given a phonetic discrimination task with speech sounds that: 1) occur in English and Spanish, 2) are exclusive to English, and 3) are exclusive to Russian, during Fall (age m = 57 months) and Spring (age m = 62 months, n = 42). In Fall, English-dominant DLLs discriminated more accurately than Spanish-dominant DLLs between English-Spanish phones and English-exclusive phones. Both groups discriminated Russian phones at or close to chance. In Spring, however, groups no longer differed in discriminating English-exclusive phones and both groups discriminated Russian phones above chance. Additionally, joint English-Spanish and English-exclusive phonetic discrimination predicted children's phonological awareness in both groups. Results demonstrate plasticity in early childhood through diverse language exposure and suggest that phonemic representation begins to emerge driven by lexical restructuring.

In Korean language, questions containing ambiguous wh-words may be interpreted as either wh-questions or yes-no questions. This study investigated 43 Korean three-year-olds’ ability to disambiguate eight indeterminate questions using prosodic and visual cues. The intonation of each question provided a cue as to whether it should be interpreted as a wh-question or a yes-no question. The questions were presented alongside picture stimuli, which acted as either a matched (presentation of corresponding auditory-visual stimuli) or a mismatched contextual cue (presentation conflicting auditory-visual stimuli). Like adults, the children preferred to comprehend questions involving ambiguous wh-words as wh-questions, rather than yes-no questions. In addition, children were as effective as adults in disambiguating indeterminate questions using prosodic cues regardless of the visual cue. However, when confronted with conflicting auditory-visual stimuli (mismatched), the quality of children's responses was less accurate than adults’ responses.

Despite the fact that in most communities interaction occurs between the child and multiple speakers, most previous research on input to children focused on input from mothers. We annotated recordings of Sesotho-learning toddlers living in non-industrial Lesotho in South Africa, and French-learning toddlers living in urban regions in France. We examined who produced the input (mothers, other children, adults), how much input was child directed, and whether and how it varied across speakers. As expected, mothers contributed most of the input in the French recordings. However, in the Sesotho recordings, input from other children was more common than input from mothers or other adults. Child-directed speech from all speakers in both cultural groups showed similar qualitative modifications. Our findings suggest that input from other children is prevalent and has similar features as child-directed from adults described in previous work, inviting cross-cultural research into the effects of input from other children.

Anticipatory coarticulation is an indispensable feature of speech dynamics contributing to spoken language fluency. Research has shown that children speak with greater degrees of vowel anticipatory coarticulation than adults – that is, greater vocalic influence on previous segments. The present study examined how developmental differences in anticipatory coarticulation transfer to the perceptual domain.

Using a gating paradigm, we tested 29 seven-year-olds and 93 German adult listeners with sequences produced by child and adult speakers, hence corresponding to low versus high vocalic anticipatory coarticulation degrees. First, children predicted vowel targets less successfully than adults. Second, greater perceptual accuracy was found for low compared to highly coarticulated speech. We propose that variations in coarticulation degrees reflect perceptually important differences in information dynamics and that listeners are more sensitive to fast changes in information than to a large amount of vocalic information spread across long segmental spans.

Despite growing research on individual differences in child bilinguals, few studies have focused on the development of syntax, included both languages, and studied newly arrived school-age migrant children. Accordingly, this study investigated the syntactic development of heritage language (HL) Syrian Arabic and L2 English by Syrian refugee children (N = 119) recently arrived in Canada using a sentence repetition task. Regression analyses showed that a partially overlapping set of child-level (input and cognitive skills) and language-level (syntactic structure) factors accounted for performance in each language. HL performance was particularly sensitive to language, cognitive, and input variables indexing cumulative HL exposure. L2 performance, however, was sensitive to cognitive and environmental variables indexing current and cumulative L2 use. Finally, despite stronger performance in Arabic than in English, results revealed interdependence between the two languages, indicating that participants with stronger syntactic abilities in their HL tended to have stronger syntactic abilities in their emerging L2.

Emotion can influence various cognitive processes. Communication with children often involves exaggerated emotional expressions and emotive language. Children with autism spectrum disorder often show a reduced tendency to attend to emotional information. Typically developing children aged 7 to 9 years who varied in their level of autism-like traits learned the nonsense word names of nine novel toys, which were presented with either happy, fearful, or neutral emotional cues. Emotional cues had no influence on word recognition or recall performance. Eye-tracking data showed differences in visual attention depending on the type of emotional cues and level of autism-like traits. The findings suggest that the influence of emotion on attention during word learning differs according to whether the children have lower or higher levels of autism-like traits, but this influence does not affect word learning outcomes.

I investigate the acquisition of affrication in Québec French (QF), where affricates are in complementary distribution with coronal stops, being realized before high front vowels and glides. Previous research on other languages shows that affricates are acquired before branching onsets, which supports the idea that complexity at the level of the segment is acquired before complexity at the level of the syllable (Lleó & Prinz, 1997). In contrast, I hypothesize that affricates are acquired after branching onsets in QF, as learners are required to understand the constraints on their distribution. I examine longitudinal data from two QF-speaking children for whom the acquisition of branching onsets has been previously analyzed (Rose, 2000). Results show that affricates are indeed acquired after branching onsets, consistent with the hypothesis. Overapplication errors indicate that children make generalizations about the phonological constraints on affrication from an early age, which is expected for the acquisition of rules.

Recent studies have found correlations between sentence-level tests and reading comprehension. However, the task demands of sentence-level tests are not well understood. The present study investigated syntactic knowledge as a construct by examining the convergent and discriminant validity of two sentence-level tasks, sentence comprehension and sentence repetition, designed to test syntactic knowledge and their relation with reading comprehension. Results from 86 Grade 6 students showed that the syntax tests were more highly correlated with each other than with tests of working memory and vocabulary. This suggests that the syntax measures tap into a set of skills that are at least partially separate from these other cognitive constructs. Furthermore, syntactic knowledge explained unique variance in reading comprehension beyond controls. The syntax tasks were working memory dependent, but working memory was not the primary reason why syntax tasks are correlated with reading comprehension.

Previous research on the effects of word-level factors on lexical acquisition has shown that frequency and concreteness are most important. Here, we investigate CDI data from 1,030 Dutch children, collected with the short form of the Dutch CDI, to address (i) how word-level factors predict lexical acquisition, once child-level factors are controlled, (ii) whether effects of these word-level factors vary with word class and age, and (iii) whether any interactions with age are due to differences in receptive vocabulary. Mixed-effects regressions yielded effects of frequency and concreteness, but not of word class and phonological factors (e.g., word length, neighborhood density). The effect of frequency was stronger for nouns than predicates. The effects of frequency and concreteness decreased with age, and were not explained by differences in vocabulary knowledge. These findings extend earlier results to Dutch, and indicate that effects of age are not due to increases in vocabulary knowledge.

This study examined the development of evaluative language in preschoolers’ oral fictional narratives using a storytelling/story-acting practice where children told stories to and for their friends. Evaluative language orients the audience to the teller's cognitive and emotional engagement with a story's events and characters, and we hypothesized that this STSA context might yield new information about the early development of this language, prior to elementary school. We analyzed 60 stories: the first and last story told by 10 children in each of three preschool classrooms (3-, 4-, and 5-year-old classes) that used STSA throughout the school year. Stories were coded for evaluative expressions and evidential expressions. Five-year-olds used significantly more evaluative language than did 3-year-olds, and children at all ages used significantly more evaluative language at the end than at the beginning of the year. The number of stories told throughout the year explained unique variance in children's evaluative language growth.

This paper addresses how input variability in the adult phonological system is mastered in the output of young children in Akan, a Kwa language spoken in Ghana, involving variability between labio-palatalized consonants and front rounded vowels. The high-frequency variant involves a complex consonant which is expected to be mastered late, while the low-frequency variant involves a front rounded vowel which is expected to be mastered relatively early. Late mastery of complex consonants was confirmed. The high-frequency labiopalatalized-consonant variant was absent at age 3 and not yet mastered even at age 5. All children produced the easier-to-produce low-frequency front-rounded-vowel variant, most at far greater frequency than in adult speech, implying that a child's output limitations can affect which variant the child targets for production. Modular theories, in which phonological plans reflect only the characteristics of adult input, fail to account for our results. Non-modular theories are implicated.

Many children grow up hearing multiple languages, learning words in each. How does the number of languages being learned affect multilinguals’ vocabulary development? In a pre-registered study, we compared productive vocabularies of bilingual (n = 170) and trilingual (n = 20) toddlers aged 17–33 months growing up in a bilingual community where both French and English are spoken. We hypothesized that because trilinguals have reduced input in French and English due to time spent hearing their third language, they would have smaller French–English vocabulary sizes than bilinguals. Trilinguals produced on average 2/3 of the number of words in these languages that bilinguals did: however, this difference was not statistically robust due to large levels of variability. Follow-up analyses did, however, indicate a relationship between input quantity and vocabulary size. Our results indicate that similar factors contribute to vocabulary development across toddlers regardless of the number of languages being acquired.

Grammatical morphology often links small acoustic forms to abstract semantic domains. Deaf and hard-of-hearing (DHH) children have reduced access to the acoustic signal and frequently have delayed acquisition of grammatical morphology (e.g., Tomblin, Harrison, Ambrose, Walker, Oleson & Moeller, 2015). This study investigated the naturalistic use of aspectual morphology in DHH children to determine if they organize this semantic domain as normal hearing (NH) children have been found to do. Thirty DHH children (M = 6;8) and 29 NH children (M = 5;11) acquiring English participated in a free-play session and their tokens of perfective (simple past) and imperfective (-ing) morphology were coded for the lexical aspect of the predicate they marked. Both groups showed established prototype effects, favoring perfective + telic and imperfective + atelic pairings over perfective + atelic and perfective + atelic ones. Thus, despite reduced access to the acoustic signal, this DHH group was unimpaired for aspectual organization.

This research revealed that the frequency of reported parent-infant singing interactions predicted 6-month-old infants’ performance in laboratory music experiments and mediated their language development in the second year. At 6 months, infants (n = 36) were tested using a preferential listening procedure assessing their sustained attention to instrumental and sung versions of the same novel tunes whilst the parents completed an ad-hoc questionnaire assessing home musical interactions with their infants. Language development was assessed with a follow-up when the infants were 14-month-old (n = 26). The main results showed that 6-month-olds preferred listening to sung rather than instrumental melodies, and that self-reported high levels of parental singing with their infants [i] were associated with less pronounced preference for the sung over the instrumental version of the tunes at 6 months, and [ii] predicted significant advantages on the language outcomes in the second year. The results are interpreted in relation to conceptions of developmental plasticity.

Children's remarkable ability to generalize beyond the input and the resulting overregularizations/ irregularizations provide a platform for a discussion of whether morphology learning uses analogy-based, rule-based, or statistical learning procedures. The present study, testing 115 children (aged 3 to 10) on an elicited production task, investigated the acquisition of the irregular distribution in the Turkish causative. Results showed that in early acquisition, to pin down the four causative suffixes, children engaged in comparisons between analogous exemplars. Thereafter to tackle the irregularity in two of the suffixes, children entertained competing hypotheses that yielded overregularizations and irregularizations. Overregularizations were instances of abstraction across the input based on type frequency; irregularizations were attempts to default to erroneous micro-generalizations. Negative correlation between errors and verb frequency suggested that recovery from errors was sensitive to token frequency. The overgeneralize-then-recover pattern that emerged in the acquisition of causative supported an integrated account of the roles of analogy, abstraction, and frequency in morphology learning.

The study adopts a naturalistic perspective, looking at the relationship between socio-economic status (SES), activities and variation sets in child-directed speech (CDS) to Spanish-speaking Argentinian toddlers. It aims to determine the effect of SES and type of activity on the proportion of words and utterances in variation sets and on the pragmatic function they serve in interaction. Thirty two children (mean: 14.3 months) and their families were audio-recorded for four hours and the middle two hours were analyzed using CLAN. We developed an automatic algorithm for variation sets extraction that compares noun, verb and adjective lexemes in successive utterances. Mixed-effects beta regression showed SES and activity type effects on the proportion of variation sets and on the pragmatic function served by variation sets. Findings revealed that the contextual variables considered impact on how interlocutors organize the information to young children at the local level of natural at home interactions.