In many so-called canonical null subject languages, null and overt subject pronouns have contrasting referential preferences: null subjects tend to maintain reference to the preceding subject while overt pronominal subjects do not. We propose that children acquire this contrast by initially restricting their attention to 1st and 2nd person…

Foreign accents can vary considerably in the degree to which they deviate from the listener's native accent, but little is known about how the relationship between a speaker's accent and a listener's native language phonology mediates adaptation. Using an artificial accent methodology, we addressed this issue by constructing a set of three…

Successful word recognition requires that listeners attend to differences that are phonemic in the language while also remaining flexible to the variation introduced by different voices and accents. Previous work has demonstrated that American-English-learning 19-month-olds are able to balance these demands: although one-off one-feature…

Languages exhibit variation at all linguistic levels, from phonology, to the lexicon, to syntax. Importantly, that variation tends to be (at least partially) conditioned on some aspect of the social or linguistic context. When variation is unconditioned, language learners regularize it -- removing some or all variants, or conditioning variant use…

Research in language development has only recently begun to focus on the inherent variability of language. Previous studies have explored at what age children begin to produce variable linguistic forms and how these forms progress through development. While children produce adult-like variation early on, some variable forms take longer to acquire…

Does language development drive language change? A common account of language change attributes the regularity of certain patterns to children's learning biases. The present study examines these predictions for change-in-progress in the use of "must" in Toronto English. Historically, modal verbs like "must" start with root…

This study investigated the developmental trajectories of three perceptual domains related to regional dialect competence: the linguistic domain, tested through an intelligibility in noise task; the objective indexical domain, tested through locality judgments and a free classification task; and the subjective indexical domain, tested through…

In learning language, children must discover how to interpret the linguistic significance of phonetic variation. On some accounts, receptive phonology is grounded in perceptual learning of phonetic categories from phonetic distributions drawn over the infant's sample of speech. On other accounts, receptive phonology is instead based on phonetic…

The phenomenon of regularization -- learners imposing systematicity on inconsistent variation in language input -- is complex. Studies show that children are more likely to regularize than adults, but adults will also regularize under certain circumstances. Exactly why we see the pattern of behaviour that we do is not well understood, however.…

In a variety of domains, adults who are given input that is only partially consistent do not discard the inconsistent portion (regularize) but rather maintain the probability of consistent and inconsistent portions in their behavior (probability match). This research investigates the possibility that adults probability match, at least in part,…

Efficient language use involves the capacity to flexibly adjust to varied pronunciations of words. Although children can contend with some accent variability before their second birthday, it is currently unclear when and how this ability reaches its mature state. In a series of five experiments, we examine the developmental trajectory of toddlers'…

In spontaneous conversations between adults, words are often pronounced with fewer segments or syllables than their citation forms. The question arises whether infant-directed speech also contains phonetic reduction. If so, infants would be presented with speech input that enables them to acquire reduced variants from an early age. This study…

Children hear new words from many different talkers; to learn words most efficiently, they should be able to represent them independently of talker-specific pronunciation detail. However, do children know what the component sounds of words should be, and can they use that knowledge to deal with different talkers' phonetic realizations? Experiment…

In this paper we investigate the effect of variable input on the acquisition of grammar. More specifically, we examine the acquisition of the third person singular marker -s on the auxiliary "do" in comprehension and production in two groups of children who are exposed to similar varieties of English but that differ with respect to adult…

Monolingual English-speaking children in the United States express social preferences for speakers of their native language with a native accent. Here we explore the nature of children's language-based social preferences through research with children in South Africa, a multilingual nation. Like children in the United States, Xhosa South African…