Effects of experience on non-native speakers’ production and perception of English vowels

This study assessed the effect of English-language experience on nonnative speakers’ production and perception of English vowels. Twenty speakers each of German, Spanish, Mandarin, and Korean, as well as a control group of 10 native English (NE) speakers, participated. The non-native subjects, who were first exposed intensively to English when they arrived in the United States (mean age"25 years), were assigned to relatively experienced or inexperienced subgroups based on their length of residence in the US (M"7.3 vs. 0.7 years). The 90 subjects’ accuracy in producing English /i > 2æ/ was assessed by having native Englishspeaking listeners attempt to identify which vowels had been spoken, and through acoustic measurements. The same subjects also identified the vowels in synthetic beat-bit (/i/-/>/) and bat-bet (/æ/-/2/) continua. The experienced non-native subjects produced and perceived English vowels more accurately than did the relatively inexperienced non-native subjects. The non-native subjects’ degrees of accuracy in producing and perceiving English vowels were related. Finally, both production and perception accuracy varied as a function of native language (L1) background in a way that appeared to depend on the perceived relation between English vowels and vowels in the L1 inventory. ( 1997 Academic Press Limited