A Probe Into The Category Perception Of Mandarin Tones Of Vietnamese And Thai Students

Language in the world, according to the existence of tone, can be divided into non-tonal language and tone language. Chinese, as a tone language, its rich tone contour is one of the difficulties for foreign language learners, which attracts specialists and scholars. The researches can be divided into two different layers:one focuses on teaching strategies of Chinese tones, and the other focuses on the acoustic theory of tones. Among these studies, we found that the non-tonal language speakers are main research objects, and within the researches of tone language, the Cantonese is the main research object. Studies on Vietnamese and Thai are rarely conducted. As for the research method, most researchers adopt a method based on the pronunciation bias of foreign Chinese learners, but the hearing-based method is seldom adopted.In this paper, using acoustic phonetic and categorical perception as the theoretical basis, we tried to investigate the perceptual pattern of Vietnam and Thai students. Compared to the perceptual pattern of Chinese students, which defined as perceptual mode of Chinese tones, we described the similarities and differences in their perceptual patterns, and discussed the effect of language experience on then-results. During the experiment, we would present a series of sounds (which are called stimuli in our experiment) to listeners, and asked them to tick the option on the questionnaire which represented the sound they heard. The stimuli were presented in two ways:singly, to determine how listeners would label them as level tone, the rising tone, the falling-rising tone, or the falling tone, and we called it "identification experiment"; and pairing or more, to determine to what extent listeners could discriminate them as a certain tone, which we called it "discrimination experiment". Among the several prototypes used in discrimination experiment, we selected the 4I-oddity task. We made out the identify rate and discriminate rate by computing the accuracy of the listeners. The identify rates are arranged along the ordinate, and the stimuli along the abscissa with the functions showing, from left to right, S1, S2to S11. In the same way, we plotted the chart of discrimination function. Compared the charts of Vietnam, Thai and Chinese listeners, and combined with some calculations, we can gave a conclusion to the effect of language background on the perception of Chinese tones reflected on Vietnam and Thai listeners.The conclusions are following:First, as native tone language speakers, Chinese listeners were better at this experiment, mainly at discriminating tones. Chinese listeners always showed higher discriminate rate at discrimination experiment than the Vietnam and the Thai. Second, the perception of Vietnam listeners is clearly influenced by their tonal language background. During the identification experiment of level tone-the falling tone continuum, we found that they cannot identify level tone and the falling tone, which showing the influence of level tone (ngang), as well as the three falling tones:tumbling tone (nga), hanging tone (huyen) and heavy tone (nang). Besides, although the perception pattern of the rising tone-the falling-rising tone continuum is quite close to the Chinese perception pattern, the sound pattern of the Vietnam is narrower than the Chinese, and they are not prefer to identify a stimulus,with a falling section from the beginning to the turning point, as a rising tone. Third, the perception of mandarin tones of Thai students, also significantly affected by the Thai language. Thai subjects of level tone, rising tone recognition model for the category, the category of subjects with China and Vietnam were different perception model, it is affected by the harmonic in Thai, high-profile. Thai subjects in mother tongue in the high-profile and perception, perception is presented by category. For there is no falling tone in Thai language and Thai participants in the rising tone perception requires starting point-a turning point and inflection point-the chromatic difference is small, at the end of perception requirement when its starting point-a turning point and inflection point-the end of the chromatic difference is bigger, in contrast, China and Vietnam subjects to the starting point of the rising tone-inflection point chromatic difference demand is bigger, the inflection point-the end of the chromatic difference is not strong. So Vietnamese and Thai students in learning mandarin tone need to be aware of the effects of negative transfer of native language, according to the effects of mother tongue, teacher can set targeted to correct them.To conclude, we analyzed the perception of Mandarin tones of Thai students and Vietnam students in an experimental method and made a comparison between their results. It is a new approach for the research of the teaching of Chinese as a foreign language. This paper provided a large amount of experimental data, which can be used as first-hand information of their perception pattern, and can also offer good proof for the influence of language background on tone perception.