Perception of English vowels by native Korean and Japanese speakers

Abstract

Native speakers of Korean and Japanese were assessed in their ability to perceive English vowels categorically. These two languages were chosen because they differ in the size of their vowel inventories with Korean containing more vowels than Japanese. The Korean vowel space is presumably partitioned more so than the Japanese and this may facilitate Korean speakers’ discrimination of English. This hypothesis is in keeping with Best’s Perceptual Assimilation Model (PAM). PAM states that non-native speakers’ discrimination of non-native sounds can be predicted by differing degrees based on whether the new non-native sounds are assimilated to one or more native phonemic categories. Further, discrimination is mediated by how well the non-native category fits the native category. Both subject groups completed the following tasks: the Categorical Discrimination Test (CDT, designed by J. Flege) which tested their discrimination of English vowels; and an assimilation task where subjects equated English vowels to their native vowels and rated each for category goodness. A’ scores were calculated for each contrast in the CDT. In addition, confusion matrices were calculated for each group. For both subject groups, the English vowels assimilated to a single vowel category were found to be more difficult to discriminate.