This study examines the comprehension of relative clauses by Chinese-speaking children, and evaluates the validity of the predictions of the Dependency Locality Theory (Gibson, 1998, 2000) and the Relativized Minimality approach (Friedmann, Belletti & Rizzi, 2009). One hundred and twenty children from three to eight years of age were tested by using a character–sentence matching task. We found a preference for subject relative clauses that persists as children grow older. This preference is predicted by the Relativized Minimality approach, but not by the Dependency Locality Theory. In addition, we observed a fine-grained class of errors in comprehension. We discuss it in the light of the head-final status of Chinese relative clauses.

This study investigates the coordination of matrix and subordinate clauses within finite complement-clause constructions. The data come from diary and audio recordings which include the utterances produced by an American English-speaking child, L, between the ages 1;08 and 3;05. We extracted all the finite complement-clause constructions that L produced and compared the grammatical acceptability of these utterances with that of the simple sentences of the same length produced within the same two weeks and with that of the simple sentences containing the same verb produced within the same month. The results show that L is more likely to make syntactic errors in finite complement-clause constructions than she does in her simple sentences of the same length or with the same verb. This suggests that the errors are more likely to arise from the syntactic and semantic coordination of the two clauses rather than limitations in performance or lexical knowledge.

Deficits in pragmatic language are central to autism spectrum disorder (ASD). Here we investigate common ground, a pragmatic language skill in which speakers adjust the contents of their speech based on their interlocutor's perceived knowledge, in adolescents with ASD and typical development (TD), using an experimental narrative paradigm. Consistent with prior research, TD participants produced shorter narrations when they shared knowledge with an interlocutor, an effect not observed at the group level in ASD. This effect was unrelated to general skills such as IQ or receptive vocabulary. In ASD, the effect was correlated with age and symptom severity: older and less severely affected participants did shorten their narratives. Several metrics (including explicit references to common ground, speech disfluencies, and communicative quality ratings) suggested that, although adolescents with ASD did not show implicit reductions in their narrative length, they were aware of common ground, and communicated differently in its presence.

This study investigates the emergence and development of the discourse-pragmatic functions of the Japanese subject markers wa and ga from a usage-based perspective (Tomasello, 2000). The use of each marker in longitudinal speech data for four Japanese children from 1;0 to 3;1 and their parents available in the CHILDES database (MacWhinney, 2000) was coded and analyzed. Findings showed that the four children initially used wa as a wh-question marker. They then gradually shifted its use to convey the proposition of given information. In contrast, the use of ga varied among the children. One child used ga with dynamic verbs in the past tense to report events he witnessed/experienced, while the other three children used it with a particular stative predicate in the present tense, expressing their subjective feeling toward referents. Findings were explained by the frequency of input to which the children had been exposed.

The number of unique words in children's speech is one of most basic statistics indicating their language development. We may, however, face difficulties when trying to accurately evaluate the number of unique words in a child's growing corpus over time with a limited sample size. This study proposes a novel technique to estimate the latent number of words from a series of words uttered by children. This technique utilizes statistical properties of the number of types as a function of the number of sampled tokens. We tested the practical effectiveness of the proposed method in the empirical data analysis of the cross-sectional and longitudinal samples. The converging empirical evidence indicates that the proposed estimator improves the accuracy of vocabulary size estimation over a set of existing estimators. Utilizing this efficient estimator, we propose a new sampling scheme for vocabulary assessment that has lower cost and higher accuracy compared to existing methods.

Before they are 3;0–3;6, children typically do not engage with peers in focused interaction, although they do with adults. With parents, children interact around the ‘here-and-now’. We hypothesize that young peers do not attempt to establish joint attention to present objects. Using the CHILDES database, we compared attention-directives produced by parents to children, children to peers, and children to parents. Of 391 English-speaking parents, 88% generated attention-directives, mostly Look!, See!, and Watch! Of 15 children (2;10–3;7) engaging in dyadic peer-interaction, only 26% produced such utterances. By comparison, 62% of 268 children (1;2–3;3) addressed such directives to parents. Interaction with peers in young children does not involve joint attention to a shared environmental focus, although it does with parents. The reason may be pragmatic: shared attention in parent–child dyads is a means to get information or help; it may seem pointless for a child to address such directives to a peer.

The study characterizes developmental trends in early Hebrew clause-combining (CC) by analyzing the interplay between linguistic form and communicative function in different interactional settings. Analysis applied to all utterances produced by three children aged 2;0–3;0 who combined two or more clauses, either self-initiated or on the basis of adult input. Ten types of CC were analyzed for marking by connectives (e.g. the Hebrew equivalents of ‘and’, ‘that’, ‘so’). Four shared consecutive developmental phases emerged: non-marking; partial marking by ‘and’ and ‘that’; use of ‘but’ and ‘because’, favored significantly in interlocutor-supported contexts; marking of adverbial relations and more varied use of še- ‘that’. These CC processes are interpreted as reflecting general properties of language development, in the form of gradually increasing specification of form–function relations under the impact of interlocutor–child interactive support combined with Hebrew-particular typological factors.

The ability to compute non-adjacent regularities is key in the acquisition of a new language. In the domain of phonology/phonotactics, sensitivity to non-adjacent regularities between consonants has been found to appear between 7 and 10 months. The present study focuses on the emergence of a posterior–anterior (PA) bias, a regularity involving two non-adjacent vowels. Experiments 1 and 2 show that a preference for PA over AP (anterior–posterior) words emerges between 10 and 13 months in French-learning infants. Control experiments show that this bias cannot be explained by adjacent or positional preferences. The present study demonstrates that infants become sensitive to non-adjacent vocalic distributional regularities between 10 and 13 months, showing the existence of a delay for the acquisition of non-adjacent vocalic regularities compared to equivalent non-adjacent consonantal regularities. These results are consistent with the CV hypothesis, according to which consonants and vowels play different roles at different linguistic levels.

This study uses a structural priming technique with young Spanish speakers to test whether exposure to a rare syntactic form in Spanish (fue-passive) would increase the production and comprehension of that form. In Study 1, 14 six-year-old Spanish speakers described pictures of transitive scenes. This baseline study revealed that fue-passives were virtually non-existent in children's spontaneous speech. Using the priming technique in Study 2, an additional 56 Spanish-speaking children were exposed to fue-passive or active picture descriptions; we varied whether children repeated the modeled form. With repetition, production of fue-passives increased past baseline usage. When not asked to repeat, comprehension and production of fue-passives was no different than chance. Results extend the existing literature by experimentally testing input effects on the production and comprehension of infrequently used constructions, further corroborating the relation between input frequency and language skill. Findings are consistent with the view that an implicit learning mechanism guides language learning.