2. VOT trumps other measures in predicting Korean children’s early mastery of tense stops Eun Jong Kong Mary E. Beckman Jan Edwards LSA2010 January 7 th ~ 10 th

3. Introduction Three-way laryngeal contrast in Korean stops lax /p, t, k/ vs. tense /p’, t’, k’/ vs. aspirated /p h, t h, k h / e.g., /tal/ moon vs. /t’al/ daughter vs. /t h al/ mask Mastery pattern of Korean stops: Transcription-based studies (Kim, Y, 1996; Kim & Pae, 2005; Kim, M, 2008) described: All (lax, tense and asp.) were mastered before three years. Tense stops appeared first in youngest children’s productions. (before 2;6) Early mastery of tense stops : Is this predictable based on the acoustic property of Korean stops? Cross-lingusitically exceptional or not?

4. Burs t Voicing Onset Short lag VOT Lead VOT Burs t Voicing Onset Burs t Voicing Onset [do'mata] tomato toast donut VOT = Burst – Voicing Onset Voice Onset Time (VOT: Lisker and Abramson 1964 ) and stop voicing/ aspiration contrast across languages Early mastery of tense stops: Is this predictable? Long lag VOT

5. LanguageLeadShort lagLong lag English (Macken & Barton 1980a) voiced voiceless Spanish (Macken & Barton 1980b) voicedvoiceless Cantonese (Clumeck et al 1981 ) unaspiratedaspirated Thai (Gandour et al 1986) voicedunaspiratedaspirated Long lag Lead [t][t] [t h ] [d] Short lag Universal order of mastery and VOT The category with short lag VOT is mastered first: the least precise articulation (Kewley-Port and Preston 1974). is achieved by the glottis opening at any time during the oral occlusion: easy to produce!

6. Short lag VOT of Korean tense stops LeadShort lagLong lag tenselax, aspirated short lag Long lag is achieved by the laryngeal muscle tenseness that delays voicing onset until the oral release. Korean tense stops: short lag VOT creaky voice quality (H1-H2) high fundamental frequency (F0): associated with H-tone accentual phrase in Seoul Korean (Cho, Jun and Ladefoged, 2002; Kagaya, 1974; Hardcastle 1974; Jun 1993). When we take a closer look at Korean tense stops … VOT values of Korean tense stops predicts the early mastery. At first glance…

7. Multiple acoustic cues of Korean stops Multiplicity of acoustic cues suggests: VOT cannot be the only predictor of Korean stop mastery order. The relative role of other cues must also be considered. We need a more sensitive quantitative model of the role of VOT in relation to F0 and H1-H2 in explaining the observed order in the transcription-based study:

8. Goal of the study This study explores the relationship between native speaker transcriptions of children’s stop productions and the three acoustic characteristics (VOT, F0, H1-H2). Mixed effects logistic regression models – Analysis (1): children’s productions transcribed accuracy as a function of age – Analysis (2): adults’ stop productions target category as a function of VOT, F0 and H1-H2 – Analysis (3): children’s stop productions transcribed category as a function of VOT, F0 and H1- H2

9. Database Materials - word-initial coronal and dorsal stops embedded in real words - following vowel contexts varied among /i, a, u/. Participants - 70 Korean-speaking children (aged 24 to 72 months) - 20 adults (10 males and 10 females: aged 18-30 years) - recruited and recorded at Seoul, Korea. Task A picture-prompted auditory word-repetition task

10. 9 /t’al.gi/ strawberry

11. 10 /ta.ram.d ʒ wi/ squirrel

12. 11 /t h a.d ʒ o/ ostrich

13. Accuracy judgment measures: – native speaker transcriptions of ‘correct’ or ‘incorrect’ in children’s stop productions. Acoustic measures: – All plosive productions also were acoustically analyzed to measure VOT, F0 and H1-H2 (voice quality measure). Analysis measures burstvoice onset VOT (sec.) frequency (Hz) H1-H2 (dB) first harmonic (H1) second harmonic (H2) frequency (Hz) amplitude (dB) 20ms F0 = 1/interval

14. Results - Analysis(1): transcribed accuracy ~ age a trend of more tense substitutions in the younger children’s productions. the highest transcribed accuracy for the tense stops in the youngest.

15. VOT: short lag VOT for tense stops Results – Analysis 2: Acoustic characteristics adults’ stops: short lag VOT F0 H1-H2 male female F0: lower F0 for lax stops H1-H2: lower H1-H2 for tense stops

16. β 1, β 2, and β 3 (coefficients) : the absolute value of coefficient is the relative contribution of each predictor in determining the dependent variable. Two sub-sets of logistic regression model were made 1.Adult-tense model predicts tense vs. non-tense (i.e., lax and asp.) 2.Adult- lax model predicts lax vs. asp. Results: Analysis (2) adults’ stops Mixed effects logistic regression model: target category (target or non-target) as a function of VOT, H1-H2 and F0

17. Results: Analysis (2) adults’ stops Steeper slope of VOT than H1-H2 1.Adult-tense model: tense (vs. non-tense) ~ VOT + F0 + H1-H2

18. Results: Analysis (2) adults’ stops 2. Adult-lax model: : lax (vs. asp) ~ VOT + F0 + H1-H2 Steeper slope of F0 than VOT

19. Children’s stops 2 year olds 4 year olds F0H1-H2VOT short lag VOT: overlap at a short lag VOT range at a younger age F0: relatively lower F0 for lax stops H1-H2: lower H1-H2 for tense stops at an older age. Results – Analysis 3: Acoustic characteristics

20. β 1, β 2, and β 3 (coefficients) : the absolute value of coefficient is the relative contribution of each predictor in determining the dependent variable. Two sub-sets of logistic regression model were made 1.Child-tense model predicts transcribed tense vs. non-tense (i.e., lax and asp.) 2.Child-lax model predicts transcribed lax vs. asp. Results: Analysis (3) children’ stops Mixed effects logistic regression model: transcribed category (transc. target or not) as a function of VOT, H1-H2 and F0

21. Results: Analysis (3) children’s stops Child-tense model: tense (vs. non-tense) ~ VOT + H1-H2 + F0 steepest slope of VOT H1-H2 VOT F0

22. not sig. Child-lax model: lax (vs. asp.) ~ VOT + H1-H2 + F0 Almost equally steep slope of VOT and F0 H1-H2VOTF0 Results: Analysis (3) children’s stops

23. Summary and Conclusion Transcription accuracy: early mastery of tense stops Acoustic characteristics: Adults’ stops – VOT: short lag VOT (tense), long lag VOT (lax and asp.) – F0: lower F0 (lax), higher (tense and asp.) – H1-H2: negative H1-H2 (tense), positive H1-H2 (lax and asp.) Children’s stops: – overlap at the three acoustic dimensions. – VOT: three categories at a short lag VOT range in a younger age. Quantitative model relating transcription categories to acoustic parameters showed that: The transcriber identified the children’s productions as tense primarily based on the VOT values of the productions. The transcribed was less influenced by F0 and H1-H2.

24. This dominant role of VOT in the transcription judgment of tense stops can explain the early mastery of tense stops – children produce a short lag VOT value before mastering a long lag VOT or a lead VOT cross-linguistically. – having a short lag VOT suffices for a transcriber to identify it as a correct production of a tense stop in Korean. Given the role of VOT in the transcription analysis, the early mastery of the Korean tense stop is not such an exceptional pattern after all. Summary and Conclusion

25. Acknowledgement This study was supported by NIDCD Grant 02932. Thanks to The children who participated in the study and the parents who gave their consent. Thank you!!! 24

26. 25 /taŋ.g ɨ n/ carrot

27. 26 /tal.ph ɛ ŋ.i/ snail

28. Summary of findings Transcription accuracy: early mastery of tense stops Acoustic characteristics Adults’ stops: – VOT: short lag VOT (tense), long lag VOT (lax and asp.) – F0: lower F0 (lax), higher (tense and asp.) – H1-H2: negative H1-H2 (tense), positive H1-H2 (lax and asp.) Children’s stops: – overlap at the three acoustic dimensions. – VOT: three categories at a short lag VOT range in a younger age. Mixed effects logistic regression models – transcribed tense vs. non-tense was primarily predicted by VOT and less by H1-H2. – transcribed lax vs. aspirated stops were explained by the F0 and VOT.

29. Korean tense stop: short lag VOT relatively high F0, creaky voice quality Transcriptions and acoustic parameters: The quantitative model of the role of VOT showed that: The transcriber identified the children’s productions of the tense target dominantly by the VOT values of the tokens, less affected by other acoustic aspects such as F0 or H1-H2. Discussion and Conclusion