The Perception, Processing and Learning of Mandarin Lexical Tone by Second Language Speakers

Field: Psychology (Social Sciences)

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 pitch to encode meaning at a lexical level (lexical tone). A key challenge for speakers of a non-tonal language learning Mandarin is to acquire this new function of pitch. This includes learning to perceive tonal categories in continuous and variable acoustic input, building this information into their lexical representations, and accessing the information during real-time processing. Given the complexity of this task, it is not surprising that lexical tone has been identified as one of the most difficult domains for L2 learners to master. The precise source of this difficulty, however, is still not well understood. The goal of this dissertation is to investigate L2 learners’ processing and use of tone at multiple levels, including speech perception, lexical processing, and word learning, in order to gain a broader understanding of the challenges in the L2 acquisition of Mandarin tone by native speakers of English. To this end, this dissertation draws on theoretical models and methodological paradigms from research in speech perception and psycholinguistics that has investigated the perception and processing of tone by native speakers, and extends these paradigms to investigate the acquisition and use of tone by L2 learners. This dissertation consists of three experiments. Experiment 1 employs identification and discrimination tasks well-established in categorical perception research to explore the extent to which L2 learners perceive tone categorically and the role of L2 proficiency in this process. Experiment 2 investigates how L2 learners process tone in the real-time comprehension of spoken Mandarin in a visual-world eye-tracking study and the relation between L2 learners’ ability in tone perception at the phonological level and their processing of tone at the lexical level. Finally, Experiment 3 explores the effects of manipulating the contrastive availability of tone during (novel) word learning on the use of tone in subsequent lexical processing. Results from Experiment 1 show that L2 learners tended to perceive tone less categorically than native speakers, and L2 proficiency was correlated with learners’ degree of categorical perception of tone. Experiment 2 shows that L2 learners weighed tonal (vs. segmental) cues less than native speakers in lexical processing and there was a correlation between L2 learners’ categorical perception of tone and their ability to use tonal (vs. segmental) cues in spoken word recognition. Results from Experiment 3 indicate that manipulating attentional focus towards tonal cues might not always be beneficial and suggests that selective focus on an individual cue may in fact be detrimental to the learning of other cues. This dissertation provides the first direct evidence showing that L2 learners’ ability to perceive tone categorically is related to their weighting of tonal cues during lexical processing, thus contributing to a better understanding of the link between processing at the phonological and lexical levels, which has been argued to be a key component in the L2 acquisition of tone (Wong & Perrachione, 2007; Cooper & Wang, 2013). Furthermore, this project tests the effectiveness of the commonly used cue-focus method for teaching words with tone in a controlled laboratory setting and raises awareness about teaching words as single entities. Overall, this dissertation contributes to research in SLA by bring conceptual insights gained from research on tone in native language processing to the study of tone in a non-native language. It also contributes to research in the fields of speech perception and psycholinguistics by probing the generalizability of findings about human language processing to L2 learners. Finally, it contributes to evidence-based L2 instruction and curricular materials by testing the effectiveness of cue-focus training.