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…

Mental rotation has emerged as an important predictor of success in Science, Technology, Engineering, and Math (STEM). By the age of 4.5 years, boys outperform girls in these abilities. Because parents use less spatial language with girls at this age (Pruden and Levine, 2017), the amount of spatial language that children are exposed to at home is…

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.…

Infants learn nouns during object-naming events--moments when caregivers name the object of infants' play (e.g., ball as infant holds a ball). Do caregivers also label the actions of infants' play (e.g., roll as infant rolls a ball)? We investigated connections between mothers' verb inputs and infants' actions. We video-recorded 32 infant-mother…

This longitudinal study examined the moderating roles of language use and gender in the relations between maternal depressive symptoms and child internalizing behaviour problems in 242 preschool children (48% girls) enrolled in Head Start centres. Teachers and parents completed the "Child Behavior Checklist for Ages 1 1/2-5." Mothers…

Recent research suggests that caregiver-child extratextual talk during shared book reading facilitates the development of preschool children's oral language skills. This study investigated the effects of the amount of picturebook text on mother-child extratextual talk during shared book reading. Twenty-four mother-child dyads (children aged…

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…

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…

Social deficits have been implicated in the language delays and deficits of children with autism (ASD); thus, the extent to which these children use language input in social contexts similarly to typically developing (TD) children is unknown. The current study investigated how caregiver input influenced the development of "wh"-question…

This dissertation examined the role of maternal input in word order acquisition of Mandarin-speaking children from the one-word to multi-word stages. Four questions about the role of maternal input were addressed: frequency effects, age-related changes, utterance type effects, and verb diversity effects. Predictions for each question were made…

This study investigated how forty-six mothers modified their talk about familiar and unfamiliar nouns and verbs when interacting with their children with Down Syndrome (DS), language impairment (LI), or typical development (TD). Children (MLUs < 2·7) were group-matched on expressive vocabulary size. Mother-child dyads were recorded playing with…

The current study examined academic language (AL) input of mothers and teachers to 15 monolingual Dutch and 15 bilingual Turkish-Dutch 4- to 6-year-old children and its relationships with the children's language development. At two times, shared book reading was videotaped and analyzed for academic features: lexical diversity, syntactic…

Via naturalistic observations, parent interview, and direct assessments, we examined language proficiency, language use, and differentiation of a 3-year, 4-month-old bilingual child exposed to Mandarin and English via the "one parent-one language" principle. Although noun versus verb dominance has been explored across verb-based…

Using an observational task followed by an experimental task with an Intermodal Preferential Looking Paradigm, we examined the effect of input on children's acquisition of class extension rules by investigating the relationship between the amount of polysemous noun-verb pairs in French-speaking 2-year-olds' input and both their spontaneous…

This study explored Mandarin-speaking mothers' referential choice in relation to informativeness. The data consisted of two Mandarin-speaking mothers' natural conversation with their children, collected when the children were between the ages of 2;2 and 3;1. The subject and object arguments of the mothers' utterances were coded for the categories…