The impact of input frequency (IF) and functional load (FL) of segments in the ambient language on the acquisition order of word-initial consonants is investigated. Several definitions of IF/FL are compared and implemented. The impact of IF/FL and their components are computed using a longitudinal corpus of interactions between thirty Dutch-speaking children (age range: 0 ; 6–2 ; 0) and their primary caretaker(s). The corpus study reveals significant correlations between IF/FL and acquisition order. The highest predictive values are found for the token frequency of segments, and for FL computed on minimally different word types in child-directed speech. Although IF and FL significantly correlate, they do have a different impact on the order of acquisition of word-initial consonants. When the impact of IF is partialed out, FL still has a significant correlation with acquisition order. The reverse is not true, suggesting that the acquisition of word-initial consonants is mainly influenced by their discriminating function.

Previous studies on children's pragmatic abilities have tended to focus on just one pragmatic phenomenon and one expressive means at a time, mainly concentrating on comprehension, and overlooking the production side. We assessed both comprehension and production in relation to several pragmatic phenomena (simple and complex standard communication acts, irony, and deceit) and several expressive means (linguistic, extralinguistic, paralinguistic). Our study involved 390 Italian-speaking children divided into three age groups: 5;0–5;6, 6;6–7;0, and 8;0–8;6. Children's performance on all tasks improved with their age. Within each age group, children responded more accurately to tasks involving standard communication than to those involving deceit and irony, across all expressive means and for both comprehension and production. Within each pragmatic phenomenon, children responded more accurately to simple acts than to complex ones, regardless of age group and expressive means, i.e., linguistic or extralinguistic. Overall results fit well with the Cognitive Pragmatics theory (Bara, 2010).

A large body of research shows that vocabulary does not develop independently of grammar, representing a better predictor of the grammatical complexity of toddlers' utterances than age. This study examines for the first time the characteristics of vocabulary and grammar development in Slovenian-speaking infants and toddlers using the Slovenian adaptation of the MacArthur-Bates Communicative Development Inventories (CDI). The sample included 512 Slovenian-speaking infants and toddlers aged 0 ; 8 to 2 ; 6. The findings suggest that between age 0 ; 8 and 2 ; 6 the development of vocabulary is best described using a quadratic function. The results also show that nouns predominate in the vocabularies of infants and toddlers of various ages; as they age and with the increasing size of their vocabularies, the share of interjections decreases and the share of verbs and adjectives increases. The size of vocabulary was also found to be related to the grammatical structure of toddlers' utterances.

This study investigated cross-linguistic influence in acquisition of a second lexicon, evaluating Samoan–English sequentially bilingual children (initial mean age 4 ; 9) during their first 18 months of school. Receptive and Expressive Vocabulary tasks evaluated acquisition of four word types: cognates, matched nouns, phrasal nouns and holonyms. Each word type had varying phonological and conceptual difference between Samoan (L1) and English (L2). Results highlighted conceptual distance between L1 and L2 as a key factor in L2 lexical acquisition. The children acquired L2 lexical items earlier if their conceptual representation was similar to that of L1. Words with greater conceptual distance between L1 and L2 emerged more slowly. This suggests that L1 knowledge influences L2 lexical consolidation for sequential bilinguals. Words that require a conceptual shift from L1 take longer to consolidate and strengthen within the L2 lexicon.

This longitudinal study examined the predictive validity of the MacArthur Communicative Developmental Inventories-Short Form (CDI-SF), a parent report questionnaire about children's language development (Fenson, Pethick, Renda, Cox, Dale & Reznick, 2000). Data were first gathered from parents on the CDI-SF vocabulary scores for seventy-six children (mean age=1 ; 10). Four years later (mean age=6 ; 1), children were assessed on language outcomes (expressive vocabulary, syntax, semantics and pragmatics) and code-related skills, including phonemic awareness, word recognition and decoding skills. Hierarchical regression analyses revealed that early expressive vocabulary accounted for 17% of the variance in picture vocabulary, 11% of the variance in syntax, and 7% of the variance in semantics, while not accounting for any variance in pragmatics in kindergarten. CDI-SF scores did not predict code-related skills in kindergarten. The importance of early vocabulary skills for later language development and CDI-SF as a valuable research tool are discussed.

The present study focuses on the characteristics of parental child-directed communication and its relationship with child language development. For this purpose, thirty-six toddlers (18 males and 18 females) and their parents were observed in a laboratory during triadic free play at ages 1 ; 3 and 1 ; 9. The characteristics of the maternal and paternal child-directed language (characteristics of communicative functions and lexicon as reported in psycholinguistic norms for Italian language) were coded during free play. Child language development was assessed during free play and at ages 2 ; 6 and 3 ; 0 using the Italian version of the MacArthur-Bates Communicative Development Inventory (2 ; 6) and the revised Peabody Picture Vocabulary Test (PPVT-R) (3 ; 0). Data analysis indicated differences between mothers and fathers in the quantitative characteristics of communicative functions and language, such as the mean length of utterances (MLU), and the number of tokens and types. Mothers also produced the more frequent nouns in the child lexicon. There emerged a relation between the characteristics of parental child-directed language and child language development.

One important mechanism suggested to underlie the acquisition of grammar is rule learning. Indeed, infants aged 0 ; 7 are able to learn rules based on simple identity relations (adjacent repetitions, ABB: “wo fe fe” and non-adjacent repetitions, ABA: “wo fe wo”, respectively; Marcus et al., 1999). One unexplored issue is whether young infants are able to process both adjacent and non-adjacent repetitions. As the previous studies always compared the two types of repetition structures directly, the ability to learn only one of them was sufficient for successful discrimination in these tasks. The present study reports two experiments, in which we test the ability of infants aged 0 ; 7 to discriminate adjacent and non-adjacent repetition structures against random controls (ABB vs. ABC and ABA vs. ABC). We show that, contrary to some previous proposals, infants aged 0 ; 7 successfully discriminate both repetition types from random controls, but show no spontaneous preference for either of them.

This study tested whether bilingual children show a lag in semantic development (the schematic–categorical shift) relative to monolingual children due to smaller vocabularies within a language. Twenty French–English bilingual and twenty English monolingual children (seven to ten years old) participated in a picture-naming task in English. Their errors were coded for schematic or categorical relations. The bilingual children made more schematic errors than monolinguals, a difference that was accounted for statistically by vocabulary score differences. This result suggests that within-language vocabulary size is one important factor in semantic development and may explain why bilingual children sometimes show a lag relative to monolingual children in one of their languages, perhaps the language in which they have received less formal instruction.

The current study examined five- and seven-year-old Mandarin-speaking children's processing of lexical tones in relation to speech segments by varying onset and rime in an oddity task (onset±rime±). Results showed that children experienced more difficulty in lexical tone oddity judgment when rimes differed across monosyllables (e.g. onset+rime−) than when onsets differed (e.g. onset−rime+). This finding suggests that vowels interfere more than consonants in lexical tone processing. Seven-year-olds consistently outperformed five-year-olds, suggesting that the growth of metalinguistic awareness and literacy exposure may play a joint role in the development of lexical tone processing skills.

We trained forty German-speaking children aged 1;8–2;0 in their comprehension of UNTER [UNDER]. The target word was presented within semantically organized input in the form of a ‘narrative’ to the experimental group and within ‘unconnected speech’ to the control group. We tested children's learning by asking them to perform an UNDER-relation before, immediately after, and again one day after the training using familiarized and unfamiliarized materials. Compared to controls, the experimental group learned better and retained more. Children with advanced expressive lexicons in particular were aided in generalizing to unfamiliarized materials by the narrative presentation. This study extends our understanding of how narrations scaffold young children's enrichment of nascent word knowledge.