Variegation - the presence of more than one supraglottal consonant per word - is a key challenge for children as they increase their expressive vocabulary toward the end of the single-word period. Here we consider the prosodic structures of target words and child forms in English, Finnish, French, Japanese and Mandarin to determine whether…

Recursive NPs are difficult to produce and late to emerge. We compare prosodic and syntactic abilities in Japanese-speaking five- and six-year-olds (n = 28) and adults (n = 10). It is reported that syntactic structure in Japanese is prosodically marked via downstep and metrical boost. Results of an elicited imitation task suggested that children…

This paper examines the acquisition of demonstratives (e.g., "that," "there") from a cross-linguistic perspective. Although demonstratives are often said to play a crucial role in L1 acquisition, there is little systematic research on this topic. Using extensive corpus data of spontaneous child speech, the paper investigates…

This study tested the claim of input-based accounts of language acquisition that children's inflectional errors reflect competition between different forms of the same verb in memory. In order to distinguish this claim from the claim that inflectional errors reflect the use of a morphosyntactic default, we focused on the Japanese verb system,…

We examined if and when English-learning 17-month-olds would accommodate Japanese forms as labels for novel objects. In Experiment 1, infants (n = 22) who were habituated to Japanese word-object pairs looked longer at switched test pairs than familiar test pairs, suggesting that they had mapped Japanese word forms to objects. In Experiments 2 (n =…

The present study investigated children's early use of verb inflection in Japanese by comparing a generativist account, which predicts that the past tense will have a special default-like status for the child during the early stages, with a constructivist input-driven account, which assumes that children's acquisition and use of inflectional forms…

Languages differ greatly in how they express causal events. In languages like Japanese, the subjects of causative sentences, or "causers," are generally animate and intentional, whereas in other languages like English, causers range widely from animate beings to inanimate objects (e.g. Wolff, Jeon & Li, 2009). This paper explores…

This study investigates the developmental trajectory of relative clauses (RCs) in Mandarin-learning children's speech. We analyze the spontaneous production of RCs by four monolingual Mandarin-learning children (0;11 to 3;5) and their input from a longitudinal naturalistic speech corpus (Min, 1994). The results reveal that in terms of the…

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…

The interpretation of floating quantifiers in Japanese requires knowledge of hierarchical phrase structure. However, the input to children is insufficient or even misleading, as our analysis indicates. This presents an intriguing question on learnability: do children interpret floating quantifiers based on a structure-dependent rule which is not…

Previous research has found that children who are acquiring argument-drop languages such as Turkish and Chinese make use of syntactic frames to extend familiar verb meanings (Goksun, Kuntay & Naigles, 2008; Lee & Naigles, 2008). This article investigates whether two-year-olds learning Japanese, another argument-drop language, make use of argument…

Young children typically do not use order-of-mention to resolve ambiguous pronouns, but may do so if given additional cues, such as gestures. Additionally, this ability to utilize gestures may be enhanced in bilingual children, who may be more sensitive to such cues due to their unique language experience. We asked monolingual and bilingual…

The present study investigated whether children's representations of morphosyntactic information are abstract enough to guide early verb learning. Using an infant-controlled habituation paradigm with a switch design, Japanese-speaking children aged 1 ; 8 were habituated to two different events in which an object was engaging in an action. Each…

Recent studies on the acquisition of semantics have argued that knowledge of the universal quantifier is adult-like throughout development. However, there are domains where children still exhibit non-adult-like universal quantification, and arguments for the early mastery of relevant semantic knowledge do not explain what causes such…

In this work, we examine a context in which a conflict arises between two roles that infant-directed speech (IDS) plays: making language structure salient and modeling the adult form of a language. Vowel devoicing in fluent adult Japanese creates violations of the canonical Japanese consonant-vowel word structure pattern by systematically…