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…

Purpose: We evaluated whether children whose inaccurate /[voiced alveolar approximant]/ productions showed evidence phonetic differentiation with /w/ at 3.5-4.5 years of age improved in /[voiced alveolar approximant]/ production over the next year more than children whose inaccurate productions did not show evidence of such differentiation. We…

There is no one-to-one mapping between speech acoustics and individual speech sounds; instead, the acoustic cues produced for individual speech sounds show wide variability both within and across talkers. Nonetheless, listeners perceive the speech of familiar and novel talkers with ease. It is theorized that listeners achieve this feat by…

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…

Musical expertise and working memory (WM) have been isolated as being the most important predictors of phonetic aptitude -- meaning the ability to imitate unfamiliar speech material. Although the link between language functions and musical expertise has been subject to many investigations, specific languages and their individual link to musical…

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…

Purpose: The purpose of this study was to determine listeners' ability to learn talker identity from speech produced with an electrolarynx, explore source and filter differentiation in talker identification, and describe acoustic-phonetic changes associated with electrolarynx use. Method: Healthy adult control listeners learned to identify…

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…

The extent to which the phonetic system of a second language is mastered varies across individuals. The present study evaluates the pattern of individual differences in late bilinguals across different phonological processes. Fifty-five late Dutch-English bilinguals were tested on their ability to perceive a difficult L2 speech contrast (the…