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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

As vogais pretônicas na fala culta do Noroeste Paulista

Silveira, Ana Amélia Menegasso da [UNESP] 17 April 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-04-17Bitstream added on 2014-06-13T18:48:54Z : No. of bitstreams: 1 silveira_aam_me_sjrp.pdf: 616424 bytes, checksum: 51fcca407998d423e9034adebcda18c8 (MD5) / Este trabalho apresenta o comportamento das vogais médias pretônicas no português culto falado na região de São José do Rio Preto, noroeste do estado de São Paulo. Nessa localidade, é comum observarmos, na pauta pretônica, a variação lingüística que envolve as vogais médias [e, o] e as altas [i, u], respectivamente, fato que gera formas alternantes como al[e]gria ~ al[i]gria e n[o]tícia ~ n[u]tícia. Denominado na literatura como Alçamento Vocálico, esse fenômeno fonológico é aqui abordado segundo o modelo teórico-metodológico da Sociolingüística Quantitativa. Assim, os fatores estruturais considerados foram: i) vogal da sílaba tônica, ii) posição da vogal pretônica em relação à sílaba tônica, iii) vogal átona seguinte, iv) consoantes precedentes, v) consoantes seguintes, vi) tipo de sílaba, vii) nasalidade, e viii) grau de atonicidade da vogal pretônica. Quanto aos fatores sociais, observamos a faixa etária do indivíduo do qual foram extraídos os dados. O corpus utilizado compreendeu 2246 contextos de vogal pretônica /e/ e 1590 contextos de vogal pretônica /o/, a partir da observação da fala de 16 informantes do sexo feminino, com nível superior de ensino, inseridos em quatro faixas etárias (16 a 25 anos; 26 a 35 anos; 36 a 55 anos; mais de 55 anos). Para a realização da análise, os dados foram submetidos ao Programa Estatístico VARBRUL e, com base nos resultados gerados pelo programa, interpretamos que a elevação das vogais, no dialeto do noroeste paulista, é resultado, sobretudo, da redução da diferença articulatória da pretônica com relação aos segmentos consonantais adjacentes. Também atribuímos à vogal contígüa à pretônica importante papel na implementação da regra do alçamento, ao acreditarmos que a presença de vogal tônica contígüa, em muitos casos, reforçou a manifestação da regra que eleva o traço de altura das vogais pretônicas. / This study presents the behaviour of the medium vowels, in pretonic position, based on data obtained from the dialects of the north-west of the State of São Paulo. In this region, pretonic mid vowels can change between mid-realisations [e, o] and high [i, u], in words like al[e]gria ~ al[i]gria and n[o]tícia ~ n[u]tícia. Referred to in the literature as Vowel Raising, this phonological phenomenon is in accordance with the theoretical model of Quantitative Sociolinguistics. The structural factors considered are: i) tonic vowel, ii) position of pretonic vowel in relation to tonic syllable, iii) subsequent vowel, iv) preceding consonant, v) subsequent consonant, vi) syllable structure, vii) nasality, and viii) grade of atonicity of the pretonic vowel. With regard to the social factor, the speaker’s age is taken into consideration. The data utilised was composed of 2246 realisations of the pretonic vowel /e/ and 1590 realisations of the pretonic vowel /o/, observed in the speech of 16 university-educated female speakers, in four age-bands (16 to 25; 26 to 35; 36 to 55 and over 55 years of age). The data was submitted to the VARBRUL statistical model. and the results showed that vowel raising occurs as a means of reducing articulatory difference between pretonic vowels and adjacent consonants. The subsequent and tonic vowels also exert an important influence on the vowel raising, confirming the application of the rule in many cases.
102

The perception and production of English vowel contrasts by Vietnamese speakers

Qin, Chuan 01 January 2010 (has links)
No description available.
103

O alçamento das vogais médio-baixas no falar da cidade de São Paulo / The mid low vowels in the São Paulo city language

Juliana Camargo Zani 28 September 2009 (has links)
Esta dissertação tem como objetivo analisar quais são os contextos que permitem ou bloqueiam o processo de alçamento vocálico das vogais médias pré-tônicas, tal como em caf[] caf[e]teria, mas não *caf[e]zinho. Assumiu-se a análise de Wetzels (1991, 1992, 1995), que propõe que este alçamento neutraliza as vogais médio-baixas através do desligamento do traço [aberto3]. Neste trabalho foram checadas três hipóteses, a saber, se a vogal seguinte a vogal médio-baixa influencia no alçamento da mesma, se o tipo de sílaba resultante da derivação influencia no alçamento ou bloqueio das vogais médias e, por fim, se a morfologia exerce influência neste fenômeno. De acordo com os dados do corpus desta dissertação, dentre as hipóteses perseguidas, a morfologia que demonstrou ter maior influência na escolha do processo de alçamento ou bloqueio das vogais médio-baixas. As outras hipóteses foram parcialmente confirmadas. Na hipótese da influencia da vogal seguinte na neutralização vocálica foi comprovado que este exerce influência, no entanto ela não ocorre pelo processo de harmonia e desarmonia. Já na hipótese da influência da sílaba resultante, apenas o contexto CVCCVC é capaz de bloquear a neutralização vocálica, enquanto os contextos que resultam CV são inertes ao processo. Os dados deste trabalho confirmaram a hipótese de Lee (1995) sobre a propriedade dos sufixos de bloquear o alçamento vocálico, e esta tese inova ao propor um estudo mais profundo dos sufixos aumentativos a fim de inseri-los a estes sufixos. Nesta tese também apresenta-se evidências de que a classificação proposta por Mateus e dAndrade (2000) de sufixos avaliativos e z-avaliativos não se mostrou aplicável aos dados do português brasileiro. / This dissertation aims to analyze the contexts that allow or block the process of vocalic raising of pretonic mid vowels as in caf[] caf[e]teria (coffee coffee bar) but not in *caf[e]zinho (small cup of coffee). It was assumed the approach proposed by Wetzels (1991, 1992, 1995), which argues that this vocalic raising neutralizes the mid/low vowels because of a disconnection of the trace [open3] In this work, three hypotheses are checked: 1) if the vowel that follows a midlow vowel has some influence on the vocalic raising of the second vowel; 2) if the type of syllable that results from the derivation has some influence on the raising or on the blocking of mid vowels; and, finally, if the morphology plays some role on this phenomenon. After analyzing the data and following the three hypotheses, it was noted that the morphology has great influence on the choice between raising and blocking the process of the mid low vowels. The other two hypotheses were partially confirmed. The hypothesis that predicts the influence of the following vowel on vocalic neutralization was proved, however it does not occur because of the process of vocalic harmony and disharmony. The hypothesis regarding the influence of the resultant syllable was partially confirmed too; it was seen that in the context of CVCCVC the vocalic neutralization is blocked, whereas in the contexts with CV as a result this blocking process does not occur. Moreover, the analysis of the data confirmed the hypothesis followed by Lee (1995) on the role played by the suffixes on blocking the vocalic raising. The study conducted for this dissertation innovates for proposing a deeper study about augmentative suffixes and for presenting evidences that the classification proposed by Mateus & dAndrade (2000) does not explain what happens in the morphology of Brazilian Portuguese.
104

Análise das postônicas não-finais em São Paulo e São Luís / An analysis of non-final post-tonic vowels in São Paulo and São Luís

Arthur Pereira Santana 29 January 2015 (has links)
Esta dissertação tem como objeto as vogais médias postônicas não-­finais do Português Brasileiro, especificamente a emergência das formas altas [] e [] e das médias-­baixas [] e [], estas últimas especificamente em dialetos do nordeste. Por meio do arcabouço teórico da Geometria de Traços, buscou-­se analisar os motivadores fonológicos que estão correlacionados à emergência de cada uma das formas das vogais. A principal hipótese que se buscou verificar foi se a emergência das vogais [] e [] na posição postônica não-­final, classificadas na literatura como resultantes de alçamento vocálico, está condicionada a correlatos fonológicos, tendo em vista que até então não se conseguiu encontrar um padrão que pudesse formalizar uma regra. Além disso, buscou-­se investigar se a emergência das formas médias-­baixas [, ] na postônica não-­final poderia ser formalizada por regra. Para tanto, realizou-­se um experimento de leitura de palavras em duas localidades, São Paulo e São Luís. A amostra foi constituída por 40 informantes com idades entre 20 e 30 anos, 20 de cada localidade. Os dados foram transcritos após uma verificação acústica de medição de formantes e posteriormente codificados para que testes estatísticos fossem aplicados. Com base nos resultados obtidos, observou-­se que (i) a emergência das formas altas se correlacionou à presença de uma vogal alta na átona final que compartilhasse o mesmo ponto de articulação que o da postônica não-­final, isto é, coronal para [] e labial para []; e que (ii) a emergência das médias-­baixas se correlacionou à presença da vogal dorsal, ou seja, da vogal baixa na átona final. Para a formalização de ambas as regras, faz-­se necessário assumir a proposta de Wetzels (2011) a respeito da neutralização como um mecanismo de mudança do valor do traço que garante a distinção em outro contexto. Entretanto, para que se pudesse capturar o fato de, para a emergência das vogais altas, além do traço de abertura, haver também correlação com o ponto de articulação da átona final e de que a produção das médias-­baixas é garantida pelo traço [aberto3], ambas as regras devem ser assimilatórias: do nó vocálico para as altas [, ] e do traço [+aberto3] para as médias-­baixas [, ]. / This thesis focuses on non-­final post-­tonic mid-­vowels, specifically, the emergence of the high [, ] and low-­mid vowels [, ], the latter characteristic of northeastern dialects. Based on the theoretical framework of Feature Geometry, it was intended to study the phonological motivators that are correlated with the emergence of each vowel form. The main hypothesis verified was if the emergence of [] and [] in non-­ final post-­tonic context, classified in the literature as a result of vowel rising phenomenon, is subject to phonological correlates, considering that up to this point no known study had found a pattern that could formalize a rule. In addition, it was intended to investigate whether the emergence of the low-­mid forms [, ] in non-­final post-­tonic context could also be formalized by rule. Therefore, a word reading experiment was ran in two cities, São Paulo and São Luis. The sample consisted of 40 informants, who were men and women aged between 20 and 30 years, 20 from each locality. Data were transcribed after an acoustic analysis of formant measurement and subsequently coded for statistical analysis. Based on the results, it was found that (i) the emergence of the high vowels was correlated with the presence of a high word final vowel that also shared the same place of articulation as the one in the non-­final post-­tonic context, i.e., coronal to [] and labial to []; and (ii) the emergence of mid-­low was correlated with the presence of the dorsal vowel, therefore, low vowel in word final position. To formalize both rules, it is necessary to assume Wetzels (2011) proposal that neutralization is a mechanism by which contrastive feature values are replaced by their opposite values. However, in order to capture the fact that, for the emergence of the high vowel, besides the open feature, theres also an association to the place of articulation of the word final vowel and that the production of mid-­low is guaranteed by the feature [open3], both rules should be assimilatory: the vocalic node for the high [, ] and the [+open3] feature to low-­ mid [, ].
105

The systematicity of vowel realizations in Hong Kong English.

January 2009 (has links)
Law, Wai Ling. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 170-180). / Abstract also in Chinese. / Title Page --- p.i / Abstract --- p.ii / 摘要 --- p.iii / Acknowledgements --- p.iv / Table of Contents --- p.v-vii / Chapter 1 Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- The focus of this thesis --- p.4 / Chapter 1.3 --- The structure of this thesis --- p.4 / Chapter Chapter 2 --- Literature Review --- p.6 / Chapter 2.1 --- A changing scene: The use of English worldwide --- p.6 / Chapter 2.1.1 --- Some old pictures and present fallacies --- p.7 / Chapter 2.1.1.1 --- Fallacy one - Native English(es) as the starting point and the end point --- p.8 / Chapter 2.1.1.2 --- Fallacy two - The stability of native models --- p.10 / Chapter 2.1.1.3 --- Fallacy three - The unarguable definite intelligibility of native varieties --- p.13 / Chapter 2.1.2 --- English as an international language - The legitimacy of New Englishes --- p.15 / Chapter 2.2 --- Theoretical frameworks and research findings on HKE --- p.18 / Chapter 2.2.1 --- Approaches in describing the systems of non-native varieties --- p.18 / Chapter 2.2.2 --- The phonology of HKE --- p.20 / Chapter 2.2.2.1 --- The significance of L1 transfer from Cantonese --- p.20 / Chapter 2.2.2.2 --- HKE as an independent phonological system --- p.26 / Chapter 2.2.2.3 --- The importance of scrutiny of phonological factors --- p.32 / Chapter 2.2.3 --- The need for a variation analysis of HKE in bridging the gap --- p.37 / Chapter 2.2.4 --- Pilot studies --- p.45 / Chapter 2.3 --- English and Cantonese Phonologies --- p.48 / Chapter 2.3.1 --- English phonology --- p.48 / Chapter 2.3.2 --- Cantonese phonology --- p.51 / Chapter 2.4 --- Research questions --- p.60 / Chapter Chapter 3 --- Methodology --- p.65 / Chapter 3.1 --- Research setting & selection of participants --- p.65 / Chapter 3.2 --- The participants --- p.69 / Chapter 3.3 --- Research design --- p.71 / Chapter 3.3.1 --- Data collection --- p.71 / Chapter 3.3.2 --- Procedures --- p.73 / Chapter 3.3.3 --- Data processing --- p.74 / Chapter 3.3.4 --- Data analysis --- p.76 / Chapter Chapter 4 --- Results --- p.85 / Chapter 4.1 --- Description of the analysis --- p.85 / Chapter 4.2 --- Independent variables - Effects of factor groups on vowel productions --- p.97 / Chapter 4.2.1 --- Proficiency --- p.97 / Chapter 4.2.2 --- Speaker --- p.98 / Chapter 4.2.3 --- Stress --- p.101 / Chapter 4.2.4 --- Number of syllables --- p.102 / Chapter 4.2.5 --- Preceding phonological environment --- p.103 / Chapter 4.2.6 --- Following phonological environment --- p.113 / Chapter 4.3 --- Dependent variables - The effects of interactions of factor groups on vowel realizations --- p.116 / Chapter 4.3.1 --- Long vowels --- p.116 / Chapter 4.3.2 --- Diphthongs --- p.118 / Chapter 4.3.3 --- Short vowels --- p.120 / Chapter 4.4 --- A comparison of behaviour of long vowels,diphthongs and short vowels --- p.123 / Chapter Chapter --- 5 Discussion --- p.129 / Chapter 5.1 --- Addressing the research questions --- p.130 / Chapter 5.2 --- Following phonological environment --- p.133 / Chapter 5.2.1 --- L1 transfer from Cantonese --- p.133 / Chapter 5.2.1.1 --- Transfer of Cantonese phonological rules and phonotactic constraints --- p.134 / Chapter 5.2.1.2 --- Effect of sonority distance --- p.140 / Chapter 5.2.1.3 --- Further evidence on interaction of Cantonese and English phonology --- p.146 / Chapter 5.3 --- Preceding phonological environment --- p.147 / Chapter 5.4 --- Stress --- p.151 / Chapter 5.5 --- Number of syllables --- p.153 / Chapter 5.6 --- Ranking of constraints in HKE phonology --- p.154 / Chapter 5.7 --- Implications of insignificance of proficiency and speaker --- p.156 / Chapter Chapter 6 --- "Implications, Limitations,Directions of Future Research and Conclusion" --- p.159 / Chapter 6.1 --- Implications --- p.159 / Chapter 6.1.1 --- Future investigations into New Englishes --- p.160 / Chapter 6.1.2 --- Language planning --- p.162 / Chapter 6.2 --- Limitations of the present study --- p.165 / Chapter 6.3 --- Directions of future research --- p.167 / Chapter 6.4 --- Conclusion --- p.169 / References --- p.170 / Appendix 1 Questionnaire of personal information --- p.181 / Appendix 2 Conversational interview prompting questions --- p.182
106

Investigating Vowel Duration as a Perceptual Cue to Voicing in the English of Native Spanish Speakers

George, Becky Jean 02 July 1996 (has links)
Researchers in the cognitive sciences, and in particular those in acoustic phonetics, investigate the acoustic properties in the speech signal that enable listeners to perceive particular speech sounds. Temporal cues have been found to convey information about the linguistic content of an utterance. One acoustic characteristic that is particularly well documented in American English is the difference in vowel duration preceding voiced and voiceless consonants, which has been found to play a role in the perception of the voicing of postvocalic word-final consonants. Research on vowel duration and its role in the perception of the voicing distinction of the following consonant has primarily involved data from native English speakers. The purpose of the present study was to investigate the vowel durations preceding word-final voiced and voiceless stops in the English production of four native Spanish speakers. This study sought to determine if differences in vowel duration are exhibited preceding voiced and voiceless consonants in the English production of the native Spanish speakers, and to determine if the vowel durations affected the perception of the voicing distinction of the postvocalic stop by four native English speakers A significant effect of voicing on the vowel durations in the English production of the native Spanish speakers was found. However, the degree of variation in the vowel lengths with respect to voicing was much less than the degree of difference exhibited in native English, and similar to the variation produced in native Spanish. The average mean difference in length with respect to the voicing of the following consonant was 17.8 msec. in the present study. In native English the mean difference between vowels preceding voiced and voiceless consonants ranges from 79 msec. to 92 msec. and in Spanish the average mean difference is 18 msec. Statistical analysis performed to quantify the contribution of vowel duration on the perception of the voicing distinction found only minimal affect. It was concluded that although the cue of vowel duration variation was present in the speech signal of this data, the listeners generally did not utilize it as a cue to the voicing distinction of the following stops.
107

Effects of Clear Speech and Linguistic Experience on Acoustic Characteristics of Vowel Production

Bianchi, Michelle 17 July 2007 (has links)
The present study investigated the hypothesis that later and/or early learners of English as a second language may exhibit an exaggerated or restricted degree of change in their production performance between clear and conversational speech styles for certain acoustic cues. Monolingual English talkers (MO), early Spanish-English bilinguals (EB) and late Spanish-English bilinguals (LB) were recorded using both clear and conversational speaking styles. The stimuli consisted of six target vowels /i, I, e, E, ae/ and /a/, embedded in /bVd/ context. All recorded target-word stimuli were isolated into words. Vowel duration was computed, and fundamental frequency (F0), and formant frequency values (F1-F4) were measured at 20%, 50%, and 80% of the vowel duration. Data from the MO and EB talkers indicates that these two groups are very similar in that they emphasize duration differences in clear speech, have similar spacing of vowels (static & dynamic properties), and have similar frequency changes in clear speech. Data from the LB talkers indicates that this group failed to emphasize differences in clear speech, particularly duration differences. In addition, the high-mid front vowels (/i, I, e/ and /E/) were found to be very poorly separated in the F1-F2 space for the LB talkers. In support of the hypothesis, the data showed that LB talkers exhibited a restricted degree of change in their production performance between clear and conversational speech styles for duration, as compared to monolingual talkers. Data analyzed for the EB talkers do not reveal systematic reductions in the degree of change in their production performance between clear and conversational speech styles, as compared to monolingual talkers.
108

A Quantitative Study Based on a Sonographic Examination of Four Vowel Sounds in Alaryngeal Speech

Schultz, Cheryl Ann 01 January 1977 (has links)
Laryngectomy, as a treatment for malignant laryngeal lesions, requires the patient to seek a substitute method of producing speech. Three types of alaryngeal speech were described: esophageal, Asai, and artificial larynx. One consideration in deciding which mode of speech is best for the patient is how closely each type of alaryngeal speech approximates normal. This investigation was an objective examination of esophageal, Asai, and artificial larynx speech as compared with normal in males and females.
109

Spectrographic Analysis of Second Language Speech: Investigating the Effects of L1

Bailey, Troy D. 28 October 1994 (has links)
Technological advances in Digital Signal Processing over the last decade have provided applied linguists with a number of computerized applications for speech analysis which can be of benefit to both the researcher and the instructor. This research project explores the techniques of speech spectrography and implements methods of acoustic phonetics to current issues in Second Language Acquisition theory. Specifically, the effects of vowel production in one's native language on the targets in a second language are investigated. Acoustic measurements of English vowels spoken by Japanese students were compared with measurements of native Japanese vowels and American English vowels. In addition, these data were compared with measurements of learner speech from a variety of native language backgrounds. Vowels from both groups of non-native English speakers showed tendencies toward the center of the vowel space. The less-experienced group showed greater token-to-token variability across height parameters than across frontedness parameters while the more experienced group showed no difference for parameters. Both groups exhibited greater frontedness than height variability between speakers which can be explained in part by differences in vocal tract size. In addition, Flege's Speech Learning Model was tested. Data did not support the hypothesis that similar vowels are more difficult to produce than different vowels. ANOVA tests showed that large LI vowel inventories do not advantage learners of languages with many vowels. The results suggest that the unique qualities of L2 speech may have more to do with developmental processes than L 1 interference.
110

Tones and vowels in Cantonese infant directed speech : hyperarticulation during the first 12 months of infancy

Xu, Nan, University of Western Sydney, College of Arts, MARCS Auditory Laboratories January 2008 (has links)
In speech, vowels and consonants are two the basic sounds that combined result in lexically meaningful items in all languages. In tone languages, changes in pitch, tone differences also make meaningful lexical distinctions in spoken words. Young infants appear to have no trouble perceiving speech sounds and their production of sounds peculiar to their particular language environment proceeds relatively smoothly and rapidly compared with adults’ acquisition of foreign languages. One way of looking at how infants come to acquire speech sounds of their first language is by examining the speech input they receive. The term infant-directed speech (IDS) has been coined to describe the special way adults and even older children speak to infants. IDS is different to adult-directed speech in various acoustic/phonetic modifications, such as exaggerated prosody, increased pitch and vowel hyperarticulation (Burnham, Kitamura, and Vollmer-Conna, 2002; Kuhl et al., 1997). The exaggerated prosody and increased pitch appear to be related to the expression of affect and gaining infants’ attention (Burnham, Kitamura, and Vollmer-Conna, 2002), whereas vowel hyperarticulation appears to be related to infants’ speech development for a number of reasons. Firstly, investigating how adults speak to foreigners, Uther, Knoll, and Burnham (2007) found that vowels are also hyperarticulated in foreigner-directed speech as in IDS, while other acoustic modifications such as exaggerated prosody and increased pitch, related to affective and attentional factors, are not present in foreigner directed speech. Secondly, Liu, Kuhl, and Tsao (2003) found a positive correlation between vowel hyperarticulation and infants’ native speech perception; mothers who hyperarticulated their vowels more had infants who were better able to discriminate native consonant contrasts.\ While vowel hyperarticulation in IDS to 6-month-olds has been investigated in both tone languages such as Mandarin (Liu et al., 2003), and non-tone languages such as Russian, Swedish, American English (Kuhl et al., 1997) and Australian English (Burnham et al, 2002), no parallel studies have been conducted on the possibility of tone hyperarticulation in tone language IDS. If vowel hyperarticulation is related to infants’ language development then tones in tone hyperarticulated. The possibility of tone as well as vowel hyperarticulation in IDS of the tone language Cantonese, and the development of hyperarticulation across the first 12 months of infancy were investigated here using a longitudinal sequential cohort design. Two groups of native Cantonese mothers were recorded speaking to their infants, the first group at 3, 6, and 9 months, and the second at 6, 9, and 12 months. The study had four main aims (1) to investigate whether tone hyperarticulation occurs in IDS in a tone language Cantonese (2) to investigate whether vowel hyperarticulation occurs in IDS in Cantonese (IDS in this languages had not yet been investigated) and if 1 and 2 are the cases (3) to compare tone and vowel hyperarticulation, and (4) to chart the development of tone and vowel hyperarticulation across the infant’s first 12 months. Contrary to previous findings of vowel hyperarticulation in English Russian, Swedish, and Mandarin IDS to 6-month-olds (Burnham et al., 2002; Kuhl et al., 1997); vowel hyperarticulation was not found for Cantonese IDS. More detailed acoustic analysis examining different dimensions of the vowel space suggest that after the infant is 3 months old, mothers’ vowels begin to be hypoarticulated in IDS compared to ADS on dimensions of back versus front, and high versus low. This pattern of results is consistent with vowel perception studies which suggest that infants have already tuned into the native vowel categories by 4 to 6 months (Polka and Werker, 1994). Tone hyperarticulation, on the other hand, was indeed present at 3 months and increased to peak at 6 to 9 months before declining at 12 months. This pattern of tone hyperarticulation across the first year of infancy is consistent with infant language development – in which attenuation of perception of non-native tones had been found between 6 to 9 months (Mattock and Burnham, 2006). Moreover, detailed phonetic analysis revealed that while the level tones are more hyperarticulated than the contour tones, tones with similar onsets and offsets (i.e., the two rising tones) are actually hypoarticulated in IDS at 9 and 12 months, a time when infants have already tuned into native tones. Finally, results from a preliminary native speech discrimination study using the same infants provide some initial indication that mothers who hyperarticulate tones more also had infants who are better able to discriminate native Cantonese consonants. Together these results suggest that in Cantonese IDS vowels are underspecified whereas tones are consistently over-specified particularly at 6 months when infants are tuning into native tones. Moreover, during this initial period of tone acquisition, only level tones are over specified while tones with similar onsets and offsets are underspecified. It seems likely that for Cantonese language environment infants, during the early stages of language acquisition, pitch information specified by level tones is sufficient for initial acquisition of information about the Cantonese tone space and that information about vowels is not so essential at this time. These studies show that there is indeed tone hyperarticulation in IDS in tone languages, and that in order to make sense of the vowel hyperarticulation data in tone languages, it is important to investigate both vowels and tones in tone languages with complex tone systems such as Cantonese, instead of simply applying Anglocentric notions of vowel hypoarticulation. / Doctor of Philosophy (PhD)

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