Phonetic similarities between English and Korean sibilants: Implications for second language acquisition

Abstract

Recent models of L2 acquisition suggest that foreign accent is determined by the degree of articulatory, acoustic, and perceptual similarity between L1 and L2 sounds. This study examined cross-language perceptual and acoustic similarities between Korean and English voiceless sibilant fricatives: Korean lax aspirated /s/ and tense unaspirated /s*/ versus English alveolar /s/ and palato-alveolar /■/. AX discrimination tests revealed that listeners perceived the non-native contrast in terms of their L1 sound system. To determine acoustic similarity among the fricatives, two acoustic parameters were measured: duration and spectral peak frequency. It was expected that the more acoustically similar two sounds were, the more they would be perceived as the same sound by listeners. However, disparate results were obtained for perceived similarity and acoustic similarity. For instance, Korean lax /s/ and English /■/ before /i/ are acoustically similar, but listeners were easily able to discriminate between them. Perceptual similarity predicts ease of acquisition better than acoustic similarity because a listener’s perceptual system incorporates how the sounds are organized in their L1 phonological system. Language teachers need to consider not just degree of similarity between pairs of sounds, but also the differences between the L1 and L2 sound systems as a whole.