An acoustic phonetic analysis of Lewis Gaelic stop consonants

1. An acoustic phonetic analysis of Lewis Gaelic stop consonants Claire Nance and Jane Stuart-Smith University of Glasgow c.nance.1@research.gla.ac.uk j.stuart-smith@englang.arts.gla.ac.uk

2. Overview • Stops in Gaelic • Approaches • Research questions • Methods • Results • Conclusions

3. Stops in Gaelic • Word initial /ph th kh/ and /p t k/ • Word medial and word final /hp ht hk/ and /p t k/ (Ladefoged et al. 1998) • (Also palatalised vs. velarised distinction)

4. Initial stops VOT Vowel voicing Closure pòg ‘a kiss’ Vowel voicing Closure bog ‘soft’

5. VOT vs. Pre-aspiration • ‘the interval between the release of the stop and the onset of glottal vibration, that is, voicing’ (Lisker and Abramson 1964:389) • ‘delay in the offset of normal voicing’ (Laver 1994:150) • Aspiration ≠ pre-aspiration (Silverman 2003)

6. Medial and final stops Pre-asp Vowel voicing Close smoc ‘smoke’ Vowel voicing Closure snog ‘nice’

7. Pre-aspiration zoom in Pre-asp Vowel voicing Close smoc ‘smoke’

8. Pre-aspiration zoom in Breathy Voice Noise Pre-asp Close Close smoc ‘smoke’

9. Approaches • Ladefoged et al. (1998) • Ní Chasaide (1985) • Sociophonetics and consonants (Foulkes and Docherty 1999)

10. Research questions • A more complete analysis than Ladefoged et al. (1998) • Is this system undergoing apparent time change?

11. Methods • Native speakers of Lewis Gaelic • 3 ‘older’ (45-55), 3 ‘younger’ (20-24) • Recording conditions • Word list data • 2257 tokens analysed • Non-parametric statistical tests

12. Measures: durational • Initial: VOT, vowel • Medial: vowel, modal voice, pre-aspiration, breathy voice, voiceless pre-aspiration, closure, VOT • Final: vowel, modal voice, pre-aspiration, breathy voice, voiceless pre-aspiration, closure

13. Measures: durational • Segmenting on the waveform in Praat Vowel Modal voice Pre-aspiration BV Noise a c a

14. Measures: dynamic noise-based • Quantification of noisiness • Anticipatory and carry-over effects (Gobl and Ní Chasaide 1999) • Adapted zero crossing rate (Gordeeva and Scobbie 2010) • Collaborating with Olga ogordeeva@gmail.com • Measure of noise from the glottis in periodic and aperiodic sections • BV measures (HNR, spectral tilt, jitter shimmer) • Standard zero crossings (Bombien 2006)

15. BP ZCR • BP filtered at 5000Hz and 1.5 x F0 • Effects of filtering (Gordeeva and Scobbie 2010:18) • Perceptual superiority of this measure ‘bus’ unfiltered ‘bus’ filtered

16. Applied to initial stops càl ‘cabbage’

17. Results: durational • VOT in initial stops • Effect of place of articulation (cf. Cho and Ladefoged 1999) n = 1285

18. Results: durational • Vowel length – the action is in the aspirated series (cf. Kessinger and Blumstein 1997) n = 642

19. Results: BP ZCR – Initial system n = 270

20. Medial system • Pre-aspiration longer in aspirated series • Some breathy voice in unaspirated • VOT ns. n = 54

21. Medial system • Vowel length (cf. Ní Chasaide 1985) n = 36 % duration of pre-aspiration word medial /ht/ according to vowel length

22. Results: BP ZCR – Medial system n = 180

23. Apparent time change • VOT longer in aspirated series for younger speakers (aspirated series again) n = 642

24. Results: BP ZCR – Initial change n = 90

25. Speech rate • Young people speak faster? • Effects on VOT (Allen et al. 2003, Pind 1995) • Ratios Burst VOT Vowel Vowel end Vowel Start Vowel Pre-aspiration Closure

26. Apparent time change • Pre-aspiration shorter • Pre-aspiration different n = 157 % modal voice, breathy voice and voiceless pre-asp in word medial stops

27. Results: BP ZCR – Medial change n = 36

28. Summary of results • YP longer VOT • YP shorter and different pre-aspiration • Benefits of a noise-based dynamic measure • Results suggest can separate phonemic categories and age groups across the syllable

29. Conclusions: systems • Support for Kessinger and Blumstein (1997): aspirated series show most variation • Phonetically aspiration and pre-aspiration are not the same • BUT aspiration functions as a system: • Vowel length • Change in younger speakers

30. Conclusions: apparent time change • Pre-aspiration results: • Diachronic instability of pre-aspiration (Silverman 2003) • Influence of English? (Contact, obsolescence…) • Greying of phonemic categories due to lexical attrition • VOT results: • Stops functioning as a system so somehow compensating? • Implications

31. References • Allen, J., Miller, L., and DeSteno, D., 2003. Individual talker differences invoice-onset-time. Journal of Acoustic Society of America, 113:1, pp. 544-552 • Bombien, L., 2006. Voicing alterations in Icelandic – a photoglottographic and acoustic investigation. In J. Harrington, C. Mooshammer, F Kleber, eds., Arbeitsberichte de sInstituts fürPhonetik der Universität Kiel, 37, pp. 63-82. Kiel: Universität Kiel • Cho, T., and Ladefoged, P., 1999. Variation and universals in VOT: evidence from 18 endangered languages. Journal of phonetics, 27, pp. 207-229 • Foulkes, P., and Docherty, G., 1999. Urban Voices. London: Arnold • Gobl, C., and Ní Chasaide, A., 1999. Voice source variation in the vowel as a function of consonantal context. In W. J. Hardcastle and N. Hewlett, eds., Coarticulation. Cambridge: CUP. pp. 122-134 • Gordeeva, O., and Scobbie, J., 2010. Preaspiration as a correlate of word-final voice in Scottish English fricatives. In S. Fuchs, M. Toda, M. Zygis, eds., Turbulent sounds: an interdisciplinary guide. Berlin: Mouton de Gruyter • Ladefoged, P., Ladefoged, J., Turk, A., St. John, S., 1998. Phonetic structures of Scottish Gaelic. Journal of the international phonetic association, 28, pp. 1-41 • Kessinger, R., and Blumstein, S., 1997. Effects of speaking rate on voice-onset-time in Thai, French, and English. Journal of Phonetics, 25:2, pp. 143-168 • Laver, J., 1994. Principles of phonetics. Cambridge: Cambridge University Press • Lisker, L., 1957. Closure duration and the intervocalic voiced-voiceless distinction in English. Language, 33:1, pp. 42-49 • Lisker, L., and Abramson, A., 1964. A cross-language study of voicing in initial stops: Acoustical measurements. Word 20, pp. 384-422 • Ní Chasaide, A., 1985. Preaspiration in phonological stop contrasts: an instrumental phonetic study. PhD thesis, University of Bangor • Pind , J . 1995. Speaking rate , voice-onset time , and quantity: The search for higher-order invariants for two Icelandic speech cues. Perception and Psychophysics, 57, pp. 291–304 • Silverman, D., 2003. On the rarity of pre-aspirated stops. Journal of linguistics 39:3, pp. 575-598

32. Mòran taing Claire Nance and Jane Stuart-Smith c.nance.1@research.gla.ac.uk j.stuart-smith@englang.arts.gla.ac.uk University of Glasgow

33. A word on breathy voice • Ní Chasaide (1985:139) sees BV as purely physiological • Some evidence to support this: no place effect • Some against: YP have more in velars

34. Word initial apparent time change • Comparison to Ladefoged et al. (1998) • Word initial /th/ and /t/

35. Word medial apparent time change • Word medial /hk/, noise and VOT

36. Closure durations • Closure durations (Lisker 1957) • Longer in aspirated series • We found significantly longer closure durations for coronals and bilabials in the aspirated series