Doctoral Dissertation Research: Nonnative Phonetic Perception in Adult L2 Learners

University Of Pittsburgh, Pittsburgh PA

Investigators

Abstract

Even with years of practice, adult learners have trouble perceiving and producing sounds in a second language (L2). Adults tend to need more focused and targeted input to achieve native-like perception and production of L2 sounds than do children. The work proposed here aims to clarify the mechanisms through which L2 perception is influenced by first language (L1) sounds, the neural basis of this perception, how learner differences can influence learning, and how different training paradigms modulate both the neural and behavioral basis of L2 sound perception. This work has the potential to clarify specifically what mechanisms affect L2 sound perception and how different types of feedback and instruction can help learners perceive differences better, allowing for better L2 instruction in the classroom and immersion settings. This study will have participants from two native speaker groups, English and Spanish, participate in a five-day training paradigm during which they will learn to discriminate Hindi sounds that do not belong to their L1 sound categories. During the five days, participants will come in to complete electroencephalogram (EEG) recordings from the scalp, baseline discrimination tasks, training, and several memory and attention individual measures. The researchers expect that the L1 will modulate the EEG waveform known as the mismatch negativity (MMN) at approximately 150-200ms after sound onset. This measure indexes early phonetic learning and previous research has shown that the waveform's amplitude can change or shift with new phonetic learning, indicating a reorganization of early acoustic and phonetic processing with new input. Furthermore, the researchers will examine how the L1 and different training and feedback paradigms influence this MMN change. The analyses will highlight previously unexplored differences in L2 behavioral and neural processing that arise from prior L1 knowledge and representations. Furthermore, final analyses will link behavioral and neural measures by correlating performance during behavioral training with neural responses to investigate the time course of adult L2 phonetic acquisition. By using both behavioral and neural methods to explore the effects of L1 influence on nonnative phonetic perception (in the first such training paradigm to examine and clarify the time course of phonetic acquisition), this work will contribute valuable information for models of L2 perception and acquisition, and relevant data for the instruction and teaching of L2 sound contrasts.