Explorations in English Vowel Space: Regional Variants and their Perception by Japanese Learners of English

Abstract

This thesis has a dual focus- on regional and social varieties of English and the implications of these variations for Japanese speakers of English as a second language. The present writer was motivated by the fact that vowels play a substantial role in constructing the sound system of each variety.The thesis first aims at clarifying the phonetic features of vowels in English, and especially examines the regional variants, supported by field research conducted in England, North America and Australia. Then, based on the studies of these regional accents, an experiment is carried out to discover how Japanese learners of English perceive the six regional variants of vowels in English.For the first purpose, in addition to surveying the general features of vowels in each major dialect, the results of four fieldwork studies by the author are presented, in order to substantiate specific features and ongoing vowel changes in the regional dialects concerned.The fieldwork in Devon in Southwestern England has shown several regional features in relation to RP including relative closeness in vowel quality between [i:] to [1], the decreased duration contrast of lax [ʊ] and tense [u:], etc. The results from fieldwork in Los Angeles and New York have yielded some kinds of vowel features peculiar to those regional variants. In the field research in LA a phenomenon of vowel merger was confirmed. Furthermore, in order to probe the degree of vowel change during the past fifty years, the data in this field research are compared with those of Peterson and Barney (1952).Two surveys in Southern Queensland are presented, investigating urban-rural differences (Brisbane and Dirranbandi, a rural town in western Queensland) and contemporary urban differences in a two-city comparison (Brisbane and Sydney). In analyzing these data taken, acoustic techniques were heavily utilized in measuring the formants or the length of vowels.For the second purpose, a vowel perception test for Japanese learners of English was devised. The characteristic of this test is that subjects perceive six different kinds of accent types in English, that is, three standard kinds (Received Pronunciation : RP, General American- GA and standard Australian) and another three non-standard kinds (Wales, Southern American and Broad Australian). The stimuli were recorded in triplets by six different speakers, and informants (Japanese students) were required to respond to distinguish which token was different from the other two, as in living-leaving-living using carrier sentences. On the whole 'standard' types were better distinguished than 'non-standard', but the major source of variation in listener's responses was found to lie in phonetic differences among particular triplets with respect to their phonological categorization in the first language.The writer believes that analysis results of this test will advance English pronunciation teaching for L2 learners because production and perception of speech sounds can be thought as two sides of the same coin.