One of the fundamental questions in the field of language acquisition is a learnability problem, which considers how learners acquire certain aspects of language which are not directly provided in the input or whose referents are not readily observable. This dissertation investigates Japanese children's acquisition of various linguistic phenomena,…

In a body of empirical research, it has been observed that young children from across different linguistic communities adhered to a particular type of nonadult interpretation of disjunction: They appear to interpret disjunction conjunctively. Through three experiments with Japanese-speaking preschoolers, we investigate the source of this nonadult…

Negation is a cornerstone of human language and one of the few universals found in all languages. Without negation, neither categorization nor efficient communication would be possible. Languages, however, differ remarkably in how they express negation. It is yet widely unknown how the way negation is marked influences the acquisition process of…

The present study investigated the role of morphosyntactic information in the acquisition of transitive and intransitive verb argument structures (VAS) in the Japanese language, which allows massive omissions of arguments and case markers. In particular, we investigated how the 'variation sets' proposed by Küntay and Slobin work in Japanese.…

Mental state terms are believed to be closely related to the development of Theory of Mind (ToM). This study focuses on mental state verbs (MSVs) and investigates how they are used by Japanese-speaking mother-child dyads compared to their English-speaking counterparts. Analyses of their spontaneous speech from the CHILDES archives show that…

Children acquire argument structure through distributional evidence, but how does this interacts with event semantics and existing verb knowledge? The current study compares verb learning in adult speakers of Japanese (where lexical causatives span wider semantic categories) and English (where alternation is more restricted). In the Fully…

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…

Syntactic bootstrapping facilitates children's initial learning of verb meanings based on syntactic information. A challenging case is the argument-drop languages, where the number of argument NPs is not a reliable cue for distinguishing between transitive and intransitive verbs. Despite this fact, the availability of syntactic bootstrapping in…

This article suggests a method to deal with cross-linguistic differences in children with Specific Language Impairment. The differences in vulnerable structures reflect typological properties of the surrounding language (e.g., Leonard 2014a, 2014b). This article adds a developmental perspective to the discussion by interpreting the vulnerable…

Much work on child sentence processing has demonstrated that children are able to use various linguistic cues to incrementally resolve temporary syntactic ambiguities, but they fail to use syntactic or interpretability cues that arrive later in the sentence. The present study explores whether children incrementally resolve filler-gap dependencies,…

In natural languages, the mapping from surface form to meaning is often quite complex, and hence the acquisition of the phenomena at the boundary between syntax and semantics has been one of the central issues in current acquisition research. This study addresses the issue of whether children have adult-like knowledge of LF "wh"-movement and its…

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…

This article reports on the development and use of the Developmental Sentence Scoring for Japanese (DSSJ), a new morpho-syntactical measure for Japanese constructed after the model of Lee's English Developmental Sentence Scoring model. Using this measure, the authors calculated DSSJ scores for 84 children divided into six age groups between 2;8…

It has long been argued that prosodic cues may facilitate syntax acquisition (e.g., Morgan, 1986). Previous studies have shown that infants are sensitive to violations of typical correlations between clause-final prosodic cues (Hirsh-Pasek et al., 1987) and that prosody facilitates memory for strings of words (Soderstrom et al., 2005). This…

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…