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,…

The acquisition of verb morphology is often studied using categorical criteria for determining the productivity of a morpheme. Applying this approach to Japanese, an agglutinative language, this study finds no consistent order for morpheme acquisition and that productivity could be explained by sampling effects. To examine morpheme acquisition…

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…

Two distinctive types of complex predicates found in English are separable verb-particle combinations ("particles") and adjectival resultatives ("ARs"). Snyder ties both to the positive setting of the Compounding Parameter ("TCP"). This predicts that during the acquisition of a [+TCP] language, any child who has…

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.…

The acoustic realization of phrasal prominence is proposed to correlate with the order of V(erbs) and O(bjects) in natural languages. The present production study with 15 talkers of Japanese (OV) and English (VO) investigates whether the speech signal contains coverbal visual information that covaries with auditory prosody, in Infant- and…

This study aims to disentangle the often-confounded effects of input frequency and morphophonological complexity in the acquisition of inflection, by focusing on simple and complex verb forms in Japanese. Study 1 tested 28 children aged 3;3-4;3 on stative (complex) and simple past forms, and Study 2 tested 30 children aged 3;5-5;3 on completive…

This longitudinal study examined the development of narrative micro- and macrostructure in Japanese-English bilingual returnee children. Returnees are children of immigrant families who move to a foreign country, spending a significant portion of their formative developmental years in the foreign majority language context before returning to their…

Languages differ in how they encode causal events, placing greater or lesser emphasis on the agent or patient of the action. Little is known about how these preferences emerge and the relative influence of cognitive biases and language-specific input at different stages in development. In these studies, we investigated the emergence of sentence…

The present dissertation extracted 17,291 questions from Aki, Ryo, and Tai and their mother's spontaneously produced speech data available in the CHILDES database (MacWhinney, 2000; Oshima-Takane & MacWhinney, 1998). The children's age ranged from 1;3 to 3;0. Their questions were coded for (1) yes/no questions that include a sentence-final…

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…

Multimodal examples of Japanese language input (such as "manga" and anime) have now become the default choice for curriculum designers, material developers, and classroom teachers to make learning "fun". More traditional written only text-based materials are now in direct competition with such materials. While there has been a…

This study analyzes the acquisition of relative clauses in Japanese to determine the semantic and functional characteristics of children's relative clauses in spontaneous speech. Longitudinal data from five Japanese children are analyzed and compared with English data (Diessel & Tomasello, 2000). The results show that the relative clauses produced…

The world's languages draw on a common set of event components for their verb systems. Yet, these components are differentially distributed across languages. At what age do children begin to use language-specific patterns to narrow possible verb meanings? English-, Japanese-, and Spanish-speaking adults, toddlers, and preschoolers were shown…