This dissertation asks what young children do with style at a time when their social and linguistic worlds begin to expand beyond the home, into the peer group. Grounded in a yearlong ethnography of a preschool classroom in the San Francisco Bay Area, I show how play moved gradually from indoors to outdoors as children got older. This shift…

Grounded in the biopsychosocial models of expressive language in autism spectrum disorder (ASD) and fragile X syndrome (FXS), this dissertation included two novel studies that examined the role of biological (i.e., physiology), psychological (i.e., autistic traits, anxiety symptoms, and child affect) and social (i.e., communication partner…

Intentional communication is a correlate of later language in children with autism spectrum disorder (ASD). A meta-analysis on two pragmatic functions of intentional communication acts (ICAs) suggested that declarative ICAs (used to comment) are correlated with language skills, but did not provide clear evidence regarding the association of…

Younger biological siblings of children with autism spectrum disorder (sibs-ASD) are at a heightened risk for developing communication disorders, such as autism spectrum disorder or language impairment. Two strategies that are theoretically motivated as potentially beneficial for sibs-ASD are follow-in comments and providing input in episodes of…

Much research in autism spectrum disorders (ASD) has focused on the development of efficacious interventions to address the core deficits of ASD. However, the heterogeneous nature of ASD complicates the development of such interventions. With great heterogeneity in the expression of ASD's core deficits, it is unlikely that there is a one size fits…

In conversation, speakers produce some words with greater intensity, longer duration, and higher fundamental frequency (F0) than other words. By making different words in a sentence more prominent than other words, a speaker can change the meaning implied by a sentence. This thesis explores the relationship between processing in the language…