When learning a language, typically-developing infants face the daunting task of learning both the sounds and the meanings of words. In this dissertation, we focus on a source of variability that complicates the one-to-one relationship between words and their meanings: wordform variability. In Chapter 1 we make a distinction between the micro…

Most sociolinguistic studies rely on apparent time, cross-sectional methods to analyze language change. On the basis of apparent time data, sociolinguists have hypothesized that cultural processes of lifespan change create predictable cycles of linguistic behavior in which adolescents lead in the use of vernacular variants and advance sound change…

It has been widely shown that infants and adults are capable of using only prosodic information to discriminate between languages. However, it remains unclear which aspects of prosody, either rhythm or intonation, listeners attend to for language discrimination. Previous researchers have suggested that rhythm, the duration and timing of speech…

To what extent does language acquisition recruit domain-general processing mechanisms? In this dissertation, evidence concerning this question is garnered from the study of individual differences in infant speech perception and their predictive value with respect to language development in early childhood. In the first experiment, variation in the…