The Longitudinal Development of Fine Phonetic Detail in Late Learners of Spanish

The present investigation analyzed early second language (L2) learning in adults. A common finding regarding L2 acquisition is that early learning appears to be necessary in order to perform on the same level as a native speaker. Surprisingly, many current theoretical models posit that the human ability to learn novel speech sounds remains active throughout the lifespan. In light of this fact, this project examines L2 acquisition in late learners with a special focus on L1/L2 use, input, and context of learning. Research regarding L1/L2 use has tended to be observational, and throughout the previous six decades of L2 research the role of input has been minimized and left largely unexplained. This study includes two production experiments and two perception experiments and focuses on the role of L1/L2 use and input in L2 acquisition in late learners in order to add to current research regarding their role in accurately and efficiently acquiring a novel speech sound. Moreover, this research is concerned with shedding light on when, if at all, during the acquisition process late learners begin to acquire a new, language-specific phonetic system, and the amount of exposure necessary in order to acquire L2 fine-phonetic detail. The experimental design presented in the present study also aims to shed light on the temporal relationship between production and perception with regard to category formation. To begin to fully understand these issues, the present study proposes a battery of tasks which were administered throughout the course of a domestic immersion program. Domestic immersion provides an understudied linguistic context in which L1 use is minimized, target language use is maximized, and L2 input is abundant. The results suggest that L2 phonetic category formation occurs at an early stage of development, and is perceptually driven. Moreover, early L2 representations are fragile, and especially susceptible to cross-language interference. Together, the studies undertaken for this work add to our understanding of the initial stages of the acquisition of L2 phonology in adult learners