A coustic Realization and Perception of English Lexical Stress by - PowerPoint PPT Presentation

A coustic Realization and Perception of English A coustic Realization and Perception of English Lexical Stress by Mandarin Learners Lexical Stress by Mandarin Learners Yuwen Lai Yuwen Lai University of British Columbia University of British Columbia University of Kansas University of Kansas Joan Sereno Sereno Joan University of Kansas University of Kansas Allard Jongman Jongman Allard University of Kansas University of Kansas 1 1

Background Background Segmental learning Segmental learning Flege 1995, James 1988, Leather & James 1991 among others 1995, James 1988, Leather & James 1991 among others Flege Suprasegmental learning Suprasegmental learning � Effect on foreign accent Effect on foreign accent � Anderson- -Hsieh et al. 1992, Munro & Derwing 1998, Hsieh et al. 1992, Munro & Derwing 1998, Trofimovich Trofimovich and and ( Anderson ( Baker, 2006) Baker, 2006) � Stress placement Stress placement � (Altmann 2006, Altmann 2006, Archibald 1997, 1998) Archibald 1997, 1998) ( � Acoustic realization and perception of cues Acoustic realization and perception of cues � (Beckman 1986, (Beckman 1986, McGory McGory 1997, Mennen 2004, 1997, Mennen 2004, Ueyama Ueyama 2001) 2001) 2 2

Prosodic features of target languages Prosodic features of target languages L1: Taiwan Mandarin Taiwan Mandarin L1: � Tone language Tone language � Phonemic role of F0 Phonemic role of F0 � Syllable Syllable- -timed rhythm timed rhythm � L2: American English American English L2: � Stress language � Stress language F0, intensity, duration, and spectral composition F0, intensity, duration, and spectral composition � Stress � Stress- -timed rhythm timed rhythm 3 3

The present study The present study Research questions Research questions How do learners utilize F0 and duration differently in How do learners utilize F0 and duration differently in production of English lexical stress? production of English lexical stress? How do learners weigh these two cues in perception? How do learners weigh these two cues in perception? Is there any correlation between production and Is there any correlation between production and perception? perception? 4 4

Acoustic study Acoustic study Stimuli Stimuli 14 word pairs: ob ob ject ject- -ob ob ject ject (noun (noun- -verb) verb) 14 word pairs: � � Participants 9 beginning and 9 advanced L2 learners � 10 native English speakers � Task Read target word in a carrier sentence, repeat the Read target word in a carrier sentence, repeat the � � target word in isolation after each sentence. target word in isolation after each sentence. only the word produced in isolation was analyzed. only the word produced in isolation was analyzed. � � Measurements Measurements Max and mean F0, duration, intensity, and F2 Max and mean F0, duration, intensity, and F2 � � 5 5

Examples Examples ob ject ob ject Native English speakers Beginning learners Advanced learners 6 6

Results Results first- -to to- -second vowel ratios second vowel ratios first nouns nouns 1.0 • All speaker groups utilize all correlates in nouns • Native speakers use max F0 and intensity to a greater extent than others 7 7

Results Results first- -to to- -second vowel ratios (verbs) second vowel ratios (verbs) first 1.0 • Learners utilize all correlates in verbs • Native speakers rely mainly on duration 8 8

Results Results stressed-to-unstressed vowel ratio, noun: v1/v2, verb: v2/v1 Intensity Mean F0 noun verb noun verb Max F0 Duration 9 9 noun verb noun verb

Results Results Max F0 Duration 1.0 noun verb noun verb Striking asymmetry in max F0 and duration realization for nouns and verbs for native speakers 10 10

Acoustic study- - summary summary Acoustic study Native speakers � marked asymmetry of realization in nouns and verbs � reduce unstressed vowels in all conditions Beginning learners � use consistent magnitudes of max F0 and duration for nouns and verbs � do not always reduce unstressed vowels Advanced learners � pattern between beginners and native speakers 11 11

Perception- - methodology methodology Perception Stimulus construction Stimulus construction d ə da � Spectral composition (dada and Spectral composition (dada and d da) ) � � Max F0 Max F0 � five first- -to to- -second vowel ratios second vowel ratios five first � Duration Duration � five first- -to to- -second vowel ratios second vowel ratios five first 12 12

Stimulus construction- - spectral composition spectral composition Stimulus construction da’DU ‘DAdu naturally produced d ə 0 da0 144 ms 197 ms duration d ə 1 197 ms pitch tier d ə 2 da1 intensity tier d ə 3 13 13

14 14 Duration Stimulus construction Stimulus construction Max F0

Perception- - Methodology Methodology Perception Participants Participants � 25 beginning, 25 advanced learners 25 beginning, 25 advanced learners � � 25 native listeners 25 native listeners � Procedure- - stress localization task stress localization task Procedure DAda daDA 15 15

Statistical analysis Statistical analysis Overall analysis (four- -way ANOVA) way ANOVA) Overall analysis (four � Between Between- -subjects factor subjects factor- - proficiency proficiency (3) (3) � � Within Within- -subjects factors subjects factors � spectral composition (2) (2) spectral composition duration (5) (5) duration max F0 (5) (5) max F0 � Dependent variable: localization responses Dependent variable: localization responses � DAda – – first syllable stressed = 1 first syllable stressed = 1 DAda daDA – – second syllable stressed = 2 second syllable stressed = 2 daDA Spectral composition has a similar effect on all proficiencies Spectral composition has a similar effect on all proficiencies ə da d ə � d da tokens receive significantly more verb responses tokens receive significantly more verb responses � 16 16

Results- - Max F0 Results Max F0 × Proficiency (*) Proficiency (*) Advanced learners strong effect daDA Native speakers gradient effect Beginning learners no effect DAda 17 17

Results- - Duration Results Duration × Proficiency (*) Proficiency (*) Beginning learners strong effect Native speakers gradient effect Advanced learners gradient effect 18 18

Perception - - Discussion Discussion Perception Native speakers Native speakers � sensitive to sensitive to max F0 and duration max F0 and duration � Beginning learners Beginning learners � sensitive to small sensitive to small duration duration differences differences � � insensitive to small max F0 differences insensitive to small max F0 differences � Advanced learners Advanced learners � sensitive to max F0 and duration, with a stronger sensitive to max F0 and duration, with a stronger � effect from max F0 max F0 cue cue effect from 19 19

Cue weighting in perception Cue weighting in perception noun verb noun noun Duration outweighs max F0 cue when in conflict 20 20

Max F0 in native production and perception in native production and perception Max F0 n.s. noun verb Perception Production Same degree of max F0 difference between use Max F0 in nouns but not in verbs stressed and unstressed syllables does not trigger same degree of responses in verb contexts (chance level) as it does in noun 21 21 contexts

Duration in native production and perception in native production and perception Duration noun verb Production Perception duration used to a greater extent verb responses require greater in verbs duration differences 22 22

General discussion General discussion Native production and perception Native production and perception � If a cue is If a cue is not used not used in production in a given context, it in production in a given context, it � does not affect perception in that context does not affect perception in that context � If a cue is If a cue is used used in production in a given context, in production in a given context, � perceptual sensitivity correlates with its magnitude perceptual sensitivity correlates with its magnitude used in production used in production 23 23

General discussion General discussion The F0 and rhythmic features in Mandarin affect the The F0 and rhythmic features in Mandarin affect the production and perception of English lexical stress production and perception of English lexical stress � Phonemic F0 Phonemic F0 � adoption of similar F0 ratios between stressed and adoption of similar F0 ratios between stressed and unstressed vowels in production (in nouns and verbs) unstressed vowels in production (in nouns and verbs) low sensitivity to small F0 differences in perception low sensitivity to small F0 differences in perception � Syllable Syllable- -based rhythm based rhythm � causes difficulties in shortening unstressed syllable but causes difficulties in shortening unstressed syllable but triggers high sensitivity in perception triggers high sensitivity in perception 24 24