Individuals differ in their ability to perceive and learn unfamiliar speech sounds, but we lack a comprehensive theoretical account that predicts individual differences in this skill. Predominant theories largely attribute difficulties of non-native speech perception to the relationships between non-native speech sounds/contrasts and…

Adults typically struggle to perceive non-native sound contrasts, especially those that conflict with their first language. Do the same challenges persist when the sound contrasts overlap but do not conflict? To address this question, we explored the acquisition of lexical tones. While tonal variations are present in many languages, they are only…

Whereas a growing amount of attention has been directed to the role of perceptual-cognitive aptitude in successful second language (L2) lexicogrammar learning, scholars have begun to investigate the same topic in the context of L2 pronunciation learning. To date, there is ongoing discussion on the mechanism underlying L2 speech learning in…

Many studies of non-native speech sound learning report a great deal of individual variability; some learners master the sounds of a second language with ease, while others struggle to perceive and produce sounds, even after years of learning the language. Although some contributions of phonological, auditory, or cognitive skills have been found…

Listeners use more than just acoustic information when processing speech. Social information, such as a speaker's race/ethnicity, can also affect listeners' understanding of the speech signal. In some cases, these social primes can facilitate perception, while in others they may inhibit perception. Indeed, a picture of an East Asian face has been…

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…

Some listeners exhibit higher sensitivity to subphonemic acoustic differences (i.e., higher speech gradiency). Here, we asked whether higher gradiency in a listener's first language (L1) facilitates foreign language learning and explored the possible sources of individual differences in L1 gradiency. To address these questions, we tested 164…

The present study investigates the time course of acoustic cue integration in the processing of the Korean three-way laryngeal stop contrast by native Korean listeners and English second language (L2) learners of Korean. As such, this study seeks to understand how native listeners and L2 learners weight and integrate fine-grained acoustic…

Purpose: Individuals vary in their ability to learn the sound categories of nonnative languages (nonnative phonetic learning) and to adapt to systematic differences, such as accent or talker differences, in the sounds of their native language (native phonetic learning). Difficulties with both native and nonnative learning are well attested in…

Substantial individual differences exist in regard to type and amount of experience with variable speech resulting from foreign or regional accents. Whereas prior experience helps with processing familiar accents, research on how experience with accented speech affects processing of unfamiliar accents is inconclusive, ranging from perceptual…

Over the last two decades, there has been an increasing interest in third language (L3) phonology (Cabrelli Amaro, 2012; Cabrelli Amaro & Wrembel, 2016). However, research so far has been primarily directed at specific stages of learning and has independently explored either production (e.g., Llama, Cardoso, & Collins, 2010; Llama &…

Purpose: Although variability of training materials has the potential to benefit the learning of lexical tones, the benefit is contingent on an individual's pitch aptitude. Previous studies did not segregate immediate learning and consolidation after an overnight interval, and little is known about how pitch aptitude differences affect…

In this dissertation, I investigated how cognitive resources as well as formal, and informal language experience impact language learning in two studies. In the first study (Chapter 2), I examined the learning of Spanish grammatical gender by Chinese international students who were studying abroad in the US. The goal of that study was to uncover…

This study investigated second language (L2) learners' perception of L2 sounds as an individual difference that predicted their improvement in pronunciation after receiving instruction. Learners were given explicit pronunciation instruction in a series of modules added to their Spanish as a foreign language curriculum and were then tested on their…

In the process of language learning, individuals must acquire different types of linguistic knowledge, such as the sounds of the language (phonemes), how these may be combined to form words (phonotactics), and morphological rules. Early and late bilinguals tend to perform like natives on second language phonological tasks that involve pre-lexical…