This study examines variation sets (VS) - structured repetitions of words in different morphosyntactic contexts - in child-directed speech (CDS) compared to adult-directed speech (ADS) across two communities (Argentinian Spanish and North American English) and socioeconomic groups. Drawing on naturalistic recordings from 101 families, results show that VS are more frequent in CDS than in ADS. In Argentinian Spanish, they are more prevalent in middle socioeconomic status (SES) households, whereas no SES-related differences emerged in the North American sample. Across languages, they were often anchored in verbs. However, SES-related differences in lexical anchoring varied by community: in Argentinian middle-SES households, CDS includes more VS anchored in adjectives, whereas in middle-SES North American English households, noun-based VS were less frequent relative to verb-based VS. Findings indicate that linguistic typology - particularly the pro-drop versus non-pro-drop distinction - and socioeconomic context are associated with the lexical distribution and organization of repetition with variation in children's everyday linguistic environments.
To communicate effectively, speakers must monitor and refine their utterances based on what their interlocutors know. Young children's use of the contrastive marker but offers a window into this ability. Using longitudinal transcripts, we examined how seven children (ages 2-5) used but to clarify messages in everyday conversations. We coded 1,446 utterances to identify clarifications addressing gaps in listener knowledge. Children rarely used but for clarification at age 2, with marked increases between ages 2 and 3. By age 3, children often used but to provide privileged information in response to adults' knowledge-gap cues. These findings raise questions about the role of conversational experience in the development of children's mentalising abilities.
Absolute gradable adjectives (e.g., dry) and relative gradable adjectives (e.g., tall) interact differently with negation, with only negated absolute gradable adjectives semantically entailing their antonyms (e.g., not dry ⊨ wet). This study examined how 4- and 5-year-old Mandarin-speaking children and adults interpreted these two types of negative expressions. Results showed that all groups interpreted negated absolute gradable adjectives as entailing their antonyms. In contrast, their interpretation of negated relative gradable adjectives diverged: 5-year-olds equated such expressions with their antonyms (e.g., not tall ≈ short), while 4-year-olds and adults treated them as semantically distinct. These findings indicate that children are sensitive to the semantic differences between absolute and relative gradable adjectives and their interactions with negation. While context-independent absolute gradable adjectives consistently prompted literal interpretations of their negation, the context dependency and semantic indeterminacy of relative gradable adjectives triggered children and adults to engage in different pragmatic reasoning about the intended meanings.
In Mandarin, the head noun in [modifier clause-de-N] encodes not only the arguments or adjuncts of the clausal verbs (e.g. "John/biscuits/plate" in the event of "John eating biscuits") but also non-argument, non-adjunct participants extended from the clausal event (e.g. "crumbs" resulting from the event of "John eating biscuits"). This article adopts a typological, multi-factorial analytic framework of noun-modifying clause constructions (NMCCs) and proposes a developmental hierarchy of three types of NMCCs: argument > adjunct > extended. We tested the hierarchy in two studies: an analysis of 728 tokens of NMCC produced by 369 children (1;2-6;9) in naturalistic corpora and a contextualised sentence repetition task conducted with 121 children (3;0-4;11) in China. Our findings show that NMCC emerges surprisingly early around 2;0 in Mandarin children. Argument NMCCs show developmental primacy in frequency and accuracy. Adjunct and extended NMCCs are acquired at a later stage, consistent with the proposed hierarchy.
Discrimination of vowel and consonant pairs is influenced by their order, known as perceptual asymmetry, and recent research suggests a similar effect for lexical tones. This study tested whether discrimination of two consecutive tones is easier when a dynamic contour tone (e.g., rising/falling) precedes a static-level tone (e.g., low/high) than vice versa. Thai-speaking children aged 4, 6, and 8 years and adults completed an AX task with four tone pairs in dynamic-static and static-dynamic orders. Adults showed no perceptual asymmetry, possibly due to ceiling effects. However, children in all three age groups discriminated dynamic-static pairs better than static-dynamic pairs. Although tone discrimination improved across age groups, the magnitude of the dynamic-static over static-dynamic advantage remained stable. These findings reveal a dynamic-static bias in tone perception that emerges before age four and remains stable into the school years. Implications for segmental asymmetries and theories of speech perception are discussed.
This study examines how late adolescent Mandarin-English heritage speakers (HSs) process different types of Mandarin pronouns in real time and how individual differences in cognitive and experiential factors modulate this process. Using a web-based visual world eye-tracking paradigm, we tested the interpretation of pronominals (ta), simplex reflexives (ziji), and complex reflexives (taziji), which differ in their reliance on narrow syntax versus syntax-discourse-semantic integration. At the group level, taziji was interpreted locally, while ziji and ta were interpreted as referring to long-distance (LD) antecedents. Working memory and inhibition modulated the processing of ziji and ta, whereas only current heritage language (HL) exposure influenced the processing of taziji. These findings indicate that domain-general cognitive resources are recruited during the resolution of pronouns involving LD and interface-level dependencies, while narrow syntactic structures are more sensitive to variation in language exposure. The results point to structural asymmetries in how cognitive and experiential factors affect real-time HL pronoun resolution.
Children produce conditional if-clauses later than other complex constructions, but the source of this delay is debated. On the conceptual complexity explanation, children acquire if-clauses later than other morphosyntactically similar constructions because they are cognitively more complex. On the pragmatic overlap explanation, children produce if-clauses infrequently because other, simpler constructions can convey similar conditional meanings. We tested the two explanations experimentally by eliciting hypothetical language in 3- to 6-year-old children and adults. Children and adults expressed hypotheticality through a variety of grammatical constructions, beyond if-clauses, in accordance with the pragmatic overlap explanation. Across age groups, if-clauses were not delayed compared to other similar constructions, against the conceptual complexity prediction. Still, the data showed important developmental differences: 3- and 4-year-old children rarely expressed conditional meanings, whereas 5- and 6-year-olds were adult-like. These findings suggest that expressing hypothetical thought develops substantially during the preschool years through interacting cognitive, pragmatic, and linguistic factors.
We investigate how Mandarin-speaking children categorize novel intransitive verbs as unergative and unaccusative using distributional information in language input. Using a Word2vec model, we examined whether distributional cues in sentences influence the categorization of novel verbs. Our results indicated that the distributional representations of novel verbs in some sentence types exhibited closer similarities to real unergatives, and the others closer to real unaccusatives, showing a distinct effect of distributional cues on verb categorization. Subsequently, we examined children's sensitivity to the distributional information in a few sentence types. The results demonstrated that distributional cues in these sentence types were useful for children to categorize novel verbs, since the categorization linked to verb meanings was reinforced by sentence types in which novel verbs occur. These findings may explain atypical behaviours of some Mandarin formal and double-syllable verbs that previous theoretical frameworks have found challenging to explain.
The "shape bias" - the tendency to generalize new nouns by their shape rather than features like colour or texture - is considered a cornerstone of early noun learning. However, the magnitude, development, and cross-cultural generality of this bias remain debated. We conducted a pre-registered meta-analysis and meta-regression of 71 studies to synthesize the evidence base. Our analysis revealed a robust overall effect, confirming the existence of a shape bias. However, this effect was characterized by extreme between-study heterogeneity (I2 = 0.95). Critically, meta-regression analyses failed to support hypothesized developmental changes, with a constant model across ages providing the most parsimonious fit. The literature is overwhelmingly dominated by studies of English-speaking children, preventing meaningful tests of cross-linguistic or cross-cultural variation. Diagnostic tests were also consistent with the possibility of publication bias, though these patterns can also arise from methodological heterogeneity and should be interpreted with caution. Together, these findings indicate that procedural variation, and potentially publication bias, more than currently testable theoretical moderators, account for the variability in the literature, severely limiting the ability to distinguish between theories of the shape bias's origins.
Research on the acquisition of language's logical connectives has generally focused on production studies (spontaneous or elicited). According to such data, parts of the logical vocabulary - in particular, conjunction and disjunction - are acquired relatively late, with adult-like production evident from age 3 for conjunction and from age 6 for disjunction. In this study, we employed the intermodal preferential looking paradigm to target the comprehension abilities of Italian-speaking toddlers of an average age of 28 months, a younger cohort than in previous studies. We collected eye-fixation data as toddlers inspected two images whilst listening to conjunctive and disjunctive sentences and analysed these data with a generalised additive model, obtaining a sequential record of the online, implicit processing of the sentences. The results indicate that toddlers discriminate between conjunction and disjunction and favour an inclusive reading of disjunction, furthermore providing evidence for the earliest comprehension of the logical connectives in ontogeny.
This study investigates how reading proficiency in an orthographically opaque foreign language (L2 English) modulates word recognition and decoding strategies of Italian adolescents with and without developmental dyslexia (DD), whose native language orthography is highly transparent. The size of the visual and phonological units that are processed while reading is modulated by the orthographic depth of the language being read. In the case of early biliterate readers, reading strategies are characterized by cross-linguistic transfer. It is an open question whether this is also the case for late biliterate bilinguals, and whether such cross-linguistic modulations are also discernible in the presence of dyslexia-related impairments, such as phonological and visual attentional span deficits. By means of eye-tracking, this study shows that cross-linguistic interactions in the reading system also emerge in late biliterates, though this effect is limited in individuals with DD.
This study examined the development of bilingual lexical networks in adolescence through word association task and network analysis. Participants were Chinese-English bilinguals in Grade 8 (middle school; aged 13-14 years) and Grade 11 (high school; aged 16-17 years). Networks were constructed based on word association responses separately for each grade and language, and structural properties of networks were computed. Results showed that from Grade 8 to Grade 11, the Chinese networks displayed increased within-group convergence while maintaining overall structural stability and small-world features. In contrast, the English networks expanded in size, with longer average shortest paths, higher local clustering, and greater modularity (Q), reflecting rapid growth and restructuring, while also exhibiting small-world features. Across grades, L1 networks remained larger and more structured than L2 networks, though the gap decreased over time, indicating increasing cross-language similarity. These findings provide new insights into bilingual lexical development during the adolescent years.
Successful use of word-formation strategies is fundamental for children's language development and vocabulary expansion (Clark, 2009, First language acquisition. Cambridge University Press). Notably, English-speaking children tend to use compounding (i.e., the joining of two roots/free morphemes) to form new words, a word-formation device highly productive in English. In contrast, Polish-speaking children rely more on derivation (i.e., the addition of an affix/bound morpheme to a root), a device which is highly productive in Polish. Less is known about how bilingual children apply word-formation devices. Thus, monolingual (English) and bilingual (English/Polish) children completed a word-formation task designed to elicit compounding (root, synthetic) and derivation (noun, verb, adjective). Results showed that bilingual children tested in Polish used more derivation and less compounding than children tested in English (monolingual, bilingual). These findings and others are discussed in terms of how bilingual children's input and testing languages may influence their use of word-formation devices.
This study investigates whether child-directed speech (CDS) exhibits enhanced segmentability compared to adult-directed speech (ADS) and explores how specific linguistic properties of each register influence computational word segmentation performance in Korean. Employing a speaker-matched corpus of naturalistic Korean CDS and ADS, we observed that Korean CDS features shorter utterances and words, lower lexical diversity, fewer hapax legomena and interjections, a greater proportion of onomatopoeia and word play, a higher frequency of one-word utterances, and lower lexical ambiguity than ADS. Computational algorithms revealed significantly higher word segmentation F-scores for CDS than ADS, suggesting that child-oriented linguistic adaptations in CDS facilitate segmentation. This observation is further supported by statistical modelling, which indicates that the enhanced segmentability in CDS is modulated by the linguistic properties of the register. We discuss the nuanced roles of these properties in shaping the performance of segmentation algorithms.
Vocabulary development is essential to early language acquisition, supporting cognitive, social, and academic growth. While much research focuses on general vocabulary, studies on multiple-meaning words - polysemous (related meanings) or homonymous (unrelated meanings) - are limited. This study focused on the expressive lexicon, examining (1) the progression of multiple-meaning word acquisition across ages 3, 4, and 5; (2) differences in acquisition between polysemous and homonymous words; and (3) the impact of a gamified intervention program on multiple-meaning word knowledge. Results showed age-related gains in multiple-meaning word knowledge, from ages 3 to 5. Polysemous words showed a trend of improvement from age 3, whereas homonymous word gains emerged only from age 4. The intervention program enhanced retrieval across all ages, with greater benefits for ages 4 and 5. These findings deepen understanding of expressive multiple-meaning vocabulary development in preschoolers and highlight age-related and semantic-category differences.
This study examines verbal backchannel behaviour in English children aged 5 years and 6 months, previously identified as late talkers (LT), compared to typically developing (TD) peers in naturalistic child-adult conversations. Data from the CHILDES Clinical English Ellis Weismer Corpus included 36 LT and 37 TD children. Verbal backchannels were analysed for quantity, type diversity, temporal distribution, and responses to opportunity points. TD children produced more verbal backchannels per minute of adult speech, especially in the middle and final conversation stages. While both groups preferred simple forms, TD children exhibited greater functional flexibility and entropy. LT children responded to fewer opportunity points, with reduced overlap and more missed chances. Despite age-appropriate standardised scores, LT children displayed persistent pragmatic deficits. These findings highlight assessing conversational skills in natural contexts and the need for targeted interventions to enhance socially coordinated language use in 5-year-old children with a late-talking history.
Efficient language screening methods are needed for older school-age children and adolescents with suspected subclinical English language weaknesses. Twenty-five English-speaking monolingual children and fourteen Spanish-English bilingual children between the ages of 9;0 and 12;9 completed a nonword repetition task, a sentence repetition task, two grammaticality judgement tasks, and a passage comprehension task were examined relative to standard scores on the Clinical Evaluation of Language Fundamentals-4. When stepwise regression analyses were performed to evaluate the utility of each measure to predict our language outcome measure, the optimal model for monolingual children consisted only of the sentence repetition task. For the group of bilingual children, the optimal model consisted of the sentence repetition task and the passage comprehension task. These results provide support for the use of sentence repetition to gain insight into the English language proficiency of school-age children and adolescents with possible subclinical English language weaknesses.
This study investigates code-switching (CS) within the noun phrase in Portuguese-German bilingual children and adolescents (aged 8-16) in German-speaking Switzerland. Using an elicited imitation task with 49 participants, we examine how linguistic and extralinguistic factors shape CS behaviour. The experiment manipulated matrix language (German vs. Portuguese), insertion type (adjective vs. noun), and adjective position (prenominal vs. postnominal). The results show that CS strategies vary depending on the grammatical properties of the matrix language. In German, prenominal adjective position-regardless of the language of the inserted adjective-was the strongest predictor of repetition accuracy. In Portuguese, the language of the adjective played a central role. We propose the Constraint Integration Model to account for the interaction between matrix-language properties and lexical features. Additionally, older age and more positive attitudes towards German increased the likelihood of producing switched utterances.
This study examines cross-linguistic influence (CLI) in the production of wh-questions by child heritage speakers of Mandarin aged 6;9 to 16;2 years in Canada. The form of CLI addressed is wh-fronting in Mandarin object-questions (where fronting is ungrammatical) and when-questions (where fronting is dispreferred). Our goals were, first, to determine whether the children front more frequently relative to their mothers; and second, to determine the impact of structural overlap between languages (operationalized by question type), relative language dominance, and age on the rate of children's fronting. Results show that the children front more frequently, and in more contexts, than do their mothers, indicating CLI. Structural overlap increased the likelihood of fronting for only some children, whereas greater dominance in English increased the likelihood of fronting for the group. Age did not correlate with changes in rates of fronting, indicating that CLI may sometimes reflect permanent divergence from the parental grammar.
This study is concerned with Albanian children speaking a nonstandard dialect who learn Standard Albanian (SA) in primary school. Our main research question is whether the phonetic characteristics of these children's first dialect are influenced by their learning of SA. We followed longitudinally 48 children in 1st, 2nd, and 5th grades (24 girls, 24 boys, 6-11 years old), some of whom grew up in a village, the others in a city. A picture-naming task was used to record four vowel features of interest, which were analyzed acoustically, then statistically with distributional regression models and generalized additive models. We found evidence that the children's first dialect was affected by SA, suggesting that by 5th grade, they were not fully proficient at distinguishing between the two systems. The four analyzed features followed different developmental trajectories, similar to adults acquiring a second dialect, and similar to feature selectivity observed in language change.
