Production of a non-contrastive sound in a second language

A speech production experiment was conducted to investigate how well native Japanese speakers can produce a non-contrastive sound in American English, namely, intervocalic alveolar flaps, and how their production varies as a function of language experience. Native Japanese speakers who have prior experience living in the US produced English sentences containing potentially flappable segments. Results showed that Japanese speakers produced alveolar flaps to varying degrees. Acoustic analysis revealed that flaps produced by Japanese speakers show properties that have previously been associated with them, such as short duration and continuous voicing. Results also showed that Japanese speakers produced alveolar flaps within words, e.g. letter, and in certain types of phrases, e.g. get on. Finally, speakers who frequently produced alveolar flaps tended to be those who arrived in the US early in their life, who stayed in the US for a long time period, and who had high scores on TOEFL iBT.