Research on "parentese," the acoustically exaggerated, slower, and higher-pitched speech directed toward infants, has mostly focused on maternal contributions, although it has long been known that fathers also produce parentese. Given recent societal changes in family dynamics, it is necessary to revise these mother-centered models of…

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,…

Recent studies have accumulated to suggest that children, akin to adults, exhibit a processing advantage for formulaic language (e.g. "save energy") over novel language (e.g. "sell energy"), as well as sensitivity to phrase frequencies. The majority of these studies are based on formulaic sequences in their canonical form. In…

This paper revisits the longstanding observation that children produce modal verbs (e.g., must, could) with their root meanings (e.g., abilities, obligations) by age 2, typically a year or more earlier than with their epistemic meanings (e.g., inferences). Established explanations for this "Epistemic Gap" argue that epistemic language…

The well-known sampling limitation of most longitudinal corpus data can be even more consequential in the study of morphosyntactic variation in child language. An analysis of caregiver input suggests that variable use in overlapping contexts may be hard to find by solely relying on corpus data collected under the sampling procedures that are…

The relationship between emotion and language in children is an emerging field of research. To carry out this type of study, researchers need to precisely manipulate the emotional parameters of the words in their experimental material. However, the number of affective norms for words in this population is still limited. To fill this gap, the…

The linguistic input children receive across early childhood plays a crucial role in shaping their knowledge about the world. To study this input, researchers have begun applying distributional semantic models to large corpora of child-directed speech, extracting various patterns of word use/co-occurrence. Previous work using these models has not…

The "wanna" facts are a classic Poverty of Stimulus (PoS) problem: "Wanna" is grammatical in certain contexts ("Who do you want PRO to play with?") but not others ("Who do you want who[strikethrough] to play with you?"). On a standard analysis, "contraction" to "wanna" is blocked by some…

Generative approaches to language have long recognized the natural link between theories of knowledge representation and theories of knowledge acquisition. The basic idea is that the knowledge representations provided by Universal Grammar enable children to acquire language as reliably as they do because these representations highlight the…

I review the classic literature in generative grammar and Marr's three-level program for cognitive science to defend the Evaluation Metric as a psychological theory of language learning. Focusing on well-established facts of language variation, change, and use, I argue that optimal statistical principles embodied in Bayesian inference models are…

Background: We discuss a free software system (Computerized Language Analysis [CLAN]) that can enable fast, thorough, and informative language sample analysis (LSA). Method: We describe methods for eliciting, transcribing, analyzing, and interpreting language samples. Using a hypothetical child speaker, we illustrate use KidEval to generate a…

This study employs the Specificity Principle to examine the relative impacts of external (input quantity at home and at school, number of books and reading frequency at home, teachers' degree and experience, language usage, socioeconomic status) and internal factors (children's working memory, nonverbal intelligence, learning-related…

Child speech is highly variable. The speech apparatus--the vocal tract, tongue, teeth, and vocal folds--develop at different rates for different children, which helps explain some of the variability in children's speech. For example, the ratio of the oral to pharyngeal cavities changes as children age, making it difficult to establish reliable…

One strategy that children might use to sort words into grammatical categories such as noun and verb is distributional bootstrapping, in which local co-occurrence information is used to distinguish between categories. Words that can be used in more than one grammatical category could be problematic for this approach. Using naturalistic corpus…

This paper provides the first evidence of maternal speech--motherese--in Wichi, an indigenous language with a complex morphology spoken in the Gran Chaco region of Argentina. The corpus consists of 22 hours of video recordings from the daily life of three children, starting from their one-morpheme utterance period (MLU = 1) to the onset of…