A comparison of native speaker and American adult learner Vietnamese lexical tones

This study investigated native and non-native speaker tone production in Northern and Southern Vietnamese. Data analysis capitalized on normalization techniques for pitch and duration in order to allow direct comparison of individual speakers. The results revealed new insight into the relative starting positions of Northern Vietnamese tones. An analysis of non-native speaker tone errors indicated particular difficulty with low fallingrising tones, as well as difficulty with tone starting positions and changes in voice quality. We elicited all speech data using a dynamic carrier sentence task in which participants produced a series of three-word utterances in response to target words that appeared individually on a computer screen in one of four colors. In this way, participants actively described a changing event, while critical components of the utterance remained constant.