Understanding how a child's language system develops into an adult-like system is a central question in language development research. An increasingly influential account proposes that the brain constantly generates top-down predictions and matches them against incoming input, with higher-level cognitive models serving to minimize prediction…

This project explores how the variation in language experiences and attitudes that Mexican American Spanish heritage speaker bilinguals in the United States have affects their speech perception in both their languages. Heritage language bilinguals speak as a first language a minority language that they have cultural ties to (e.g., Spanish in the…

In this study, we propose a hypothesis that domain-general auditory processing, a perceptual anchor of L1 acquisition, can serve as the foundation of successful post-pubertal L2 learning. This hypothesis was tested with 139 post-pubertal L2 immersion learners by linking individual differences in auditory discrimination across multiple acoustic…

This dissertation examines the development of the internal structure of the Korean syllable by adult Korean learners whose native language is English. Prior research has identified the prominence of the body constituent in Korean and the rime constituent in English. The current study focuses on the acquisition of the body unit by English speakers…

English-speaking children use plural morphology from around the age of 2, yet often omit the syllabic plural allomorph /-[schwa]z/ until age 5 (e.g., "bus(es)"). It is not clear if this protracted acquisition is due to articulatory difficulties, low input frequency, or fricative-final words (e.g., "bus," "nose") being…

Intonation plays an integral role in comprehending spoken language. Listeners can rapidly integrate intonational information to predictively map a given pitch accent onto the speaker's likely referential intentions. We use mouse tracking to investigate two questions: (a) how listeners draw predictive inferences based on information from…

This dissertation investigates how English-speaking second language (L2) learners of Mandarin perceive, process and learn Mandarin lexical tones. While most languages use modulations in pitch (intonation) to convey meanings at the phrasal and sentential levels, a number of languages, including Mandarin, also use suprasegmental features such as…

Purpose: Successful speech processing depends on our ability to detect and integrate multisensory cues, yet there is minimal research on multisensory speech detection and integration by children. To address this need, we studied the development of speech detection for auditory (A), visual (V), and audiovisual (AV) input. Method: Participants were…

One hypothesis to explain perceptual narrowing in speech perception is the distributional learning account. This account claims that both infants and adults are able to infer the number of phonemic categories through observations of frequency distributions of individual phones in their speech input (Maye, Werker, & Gerken, 2002). Although the…

Language exposure plays a large role in language acquisition, and bilingual children must acquire both of their languages in environments that typically include abundant speech variability. The specific goals of this dissertation were to examine how speech exposure affected phonological retuning and lexical access in bilingual children's second…

Deaf and Hard of Hearing (DHH) children need to master at least one language (spoken or signed) to reach their full potential. Providing access to a natural sign language supports this goal. Despite evidence that natural sign languages are beneficial to DHH children, many researchers and practitioners advise families to focus exclusively on spoken…

How does phonological development differ in children exposed to one versus two variants of a single language? If children receive mixed evidence for a phonological contrast (i.e., one language variant in the environment maintains a contrast while another neutralizes it), will they treat this contrast as noncontrastive (i.e., as allophonic)? Or…

Models of language acquisition are constrained by the information that learners can extract from their input. Experiment 1 investigated whether 3-month-old infants are able to encode a repeated, unsegmented sequence of five syllables. Event-related-potentials showed that infants reacted to a change of the initial or the final syllable, but not to…

This study investigated the role of inhibition in second language (L2) learners' phonological processing. Participants were Spanish learners of L2 English and American learners of L2 Spanish. We measured inhibition through a retrieval-induced inhibition task. Accuracy of phonological representations (perception and production) was assessed through…

The early relationship between children's emerging articulatory abilities and their capacity to process speech input was investigated, following recent studies with English-learning infants. Twenty-six monolingual Italian-learning infants were tested at 6 months (no consistent and stable use of consonants, or vocal motor schemes [VMS]) and at the…